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BirEVJSTE

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Translated by Edward Epstean

DOVER PHOTOGRAPHY
COLLECTIONS

New York in the Thirties, Berenice Abbott. (22967-X) $4.50
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Photographic Views of Sherman’s Campaign, George N. Barnard.
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Old New York in Early Photographs, 1853-1901, Mary Black.

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Alvin Langdon Coburn, Photographer: An Autobiography, Alvin Lang-
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Cruickshank’s Photographs of Birds of America, Allan D. Cruickshank.
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Greenwich Village: A Photographic '"'jide, Edmund T. Delaney and
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Photo-Secession, Robert Doty. (23588-2) $5.00

Early American Gravestone Art, Francis Y. Duval and Ivan B. Rigby.
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Great News Photos and the Stories Behind Them, John Faber.

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History of Photography, Josef Maria Eder. (23586-6) $10.00
San Francisco in the 1850s, G.R. Fardon. (23459-2) $3.00
New York in the Forties, Andreas Feininger. (23585-8) $6.00
Stone and Man: A Photographic Exploration, Andreas Feininger.
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A New EnglandTown in Early Photographs, Edmund V. Gillon, Jr. (ed.).
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People and Crowds: A Photographic Album for Artists and Designers,
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Old Philadelphia in Early Photographs, 1839-1914, Robert F. Looney
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Children of the Past in Photographic Portraits, Alison Mager (ed.).
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( continued on inside back cover )

JOSEF MARIA EDER

HISTORY OF
PHOTOGRAPHY

By JOSEF MARIA EDER

TRANSLATED BY

EDWARD EPSTEAN

HON. F. R. P. S.

DOVER PUBLICATIONS, INC.
NEW YORK

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Preface to the Third Edition (1905-)

What is probably the earliest authoritative source of the history of
our knowledge and appreciation of the physics of light and its action
reaches us through Priestley in his History and Present State of Dis-
coveries Relating to Vision, Light and Colours (1772; German edition,
1775). In its pages we find some scant observations on the chemical
action of light. Ebermaier’s Versuch einer Geschichte des Lichtes und
dessen Einfluss auf den menschlichen Korper ( 1 799) , as well as Horn’s
Vber die Wirkungen des Lichtes auf den lebenden menschlichen
Korper mit Ausnahme des Sehens (1799), contains many historical
notes which, however, are chiefly of interest to students of physiology.

Concerning other early theories of light in general, as well as regard-
ing its chemical action, much of importance may be found in Johann
Carl Fischer’s extensive work Geschichte der Physik ( 1801 -6, 8 vols.),
upon which I have drawn largely in the preparation of the present work.
Gmelin’s Geschichte der Chemie (1799) and Fischer’s Physikalisches
W orterbuch (1801-25, 9 vols.) are valuable works of the same char-
acter. The prize essays of Link and Heinrich, Vber die Natur des
Lichtes (1808), deservedly distinguished by the Academy of Sciences
of St. Petersburg, have furnished very excellent and valuable contribu-
tions, not only giving their own personal observations but also re-
porting with painstaking care the earlier contributions on this subject.
This work was included, almost in its entirety, in Landgrebe’s excellent
collected works Vber das Licht ( 1834) . Landgrebe brought to us, in a
general way, the same early sources and added other enlarged literary
contributions up to 1833, and gave us a detailed index containing nu-
merous early references and notes on the subject. A valuable contribu-
tion to the literature of photochemistry is offered in G. Suckow’s Com-
mentatio physic a de lucis effectibus chemicis (Jena, 1828), which bears
the motto “nihil luce obscurius” (nothing is darker than light) and is
dedicated to Dobereiner.This work was awarded a prize by the Univer-
sity of Jena. Later than Suckow we have independent essays on the early
sources by J. Fiedler, whose Latin dissertation De lucis effectibus che-
micis in corpora anorganic a (1835) is edited with careful skill worthy
of the highest commendation. This author relies much more on Priestley,
in his History and Present State of Discoveries Relating to Vision, Light

PREFACE TO THE THIRD EDITION (1905)

and Colours (1772; German ed., 1775), than on those who preceded
him, and in some parts of his historical treatment far excels his predeces-
sors. Another important contribution to the study of photochemistry in
the nineteenth century is Karsten’s “Literaturbericht der Photoche-
mie,” which appeared in the Fortschritten der Physik pro 184.5. At this
point I feel compelled to remark that the existing textbooks were quite
inadequate and of little service in my researches among the early
sources. Thus the celebrated works of Hunt, Researches on Light
(1844), and Becquerel’s La Lumiere offer little of value in their
historical notes, while W. J. Harrison’s History of Photography
(1888) is concerned in a superficial way with the years preced-
ing Daguerre, while it is well known that Fouque’s history, La Verite
sur V invention de la photo graphie (1867) confines itself entirely to the
inventions of Niepce.

Facing this deficiency of material for the formation of the ground-
work for my Geschichte der Photochemie, I was compelled to search
through book after book and innumerable periodical publications, cov-
ering subjects with the oddest titles, in order to find the existing refer-
ences to photochemical subjects. I published the first fragment of my
researches into the historical source of information in the Photograph-
ische Korrespondenz (1881). This was followed, in 1890, by the first
edition of my Geschichte der Photochemie, which appeared as the first
part of my complete and specialized Handbuch der Photographie,
presenting for the first time these studies as a connected and coherent
unit. With this work I may safely claim to have traced the history of
photography in the pre-Daguerre period. How much more complete
my studies of the historical sources of this period are than those of my
predecessors is proved by a simple comparison. It may be noted here
that all later writers on the history of photography base their works on
my studies of the sources of information.

Major General J. Waterhouse (London, 1901-3), pursued a series
of further studies of these sources, following my basic publication.
These included: “Notes on the Early History of the Camera Obscura”
{Photographic Journal, Vol. XXV, No. 9); “Notes on Early Tele-
Dioptric Lens-Systems and the Genesis of Telephotography” {Photo-
graphic Journal, V ol. XXVI, No. i);“Historical Notes on Early Photo-
graphic Optics” {Journal of the Camera Club, September, 1902) ; and
“The History of the Development of Photography with the Salts of

PREFACE TO THE THIRD EDITION (1905) vii

Silver” ( Photographic Journal, Vol. XLIII, June, 1903), all of which
embody extremely serious and exact investigations.

There were others who made use of my studies of historical sources,
but without mentioning whence their information was derived. Writ-
ing at second-hand in many other cases, without a fundamental knowl-
edge of the subject, they mixed facts and falsehoods without discrimina-
tion or judgment, as I proved in the Photographische Korrespondenz
(1891, pp. 148, 254). I think it best not to concern myself any further
with them. On the other hand, the books of W. Jerome Harrison, A
History of Photography (Bradford, 1888), and John Werge, The Evo-
lution of Photography (London, 1890), are well-written and conscien-
tious efforts, at least as far as concerns the participation of England and
America in the invention of photography in the nineteenth century.
Interestingly written, but limited to a very small group of the inventors
of photography, is the work of R. Colson, Memoires originaux des
createurs de la photographie (Paris, 1 898) . In this work only the biog-
raphies and experiments of Joseph Nicephore Niepce, Daguerre,
Bayard, Talbot, Niepce de Saint- Victor, and Poitevin are dealt with in
considerable detail, and no mention is made of other inventors. It is
unfortunate that the share of German and Austrian inventors in the
development of photography seems to have been largely unknown to
these English and French historians. Therefore, in this present work
I have given special attention to the development of the history of
photography from an international viewpoint, especially later than
Daguerre, having first devoted myself to a minute study of the sources
of information in order to obtain the greatest objectivity in the con-
ception and writing of my Geschichte der Photographie.

There were three stages in the development of my Geschichte der
Photographie. The first was the period to the beginning of the eight-
eenth century; this fragment, as was mentioned above, was published
in 1881. In 1890 I published (see above) the development of photo-
chemistry up to Daguerre and Niepce. Then followed the first authori-
tative and exhaustive treatment of the general field of photography,
with accurate references to the literature and historical sources, in my
Ausfiihrliches Handbuch der Photographie, which served as the
groundwork for my history of the modern photographic processes.
With this material in hand, I was enabled for the first time to attempt,
in this (third) edition of my history, to present the history of the in-

viii PREFACE TO THE THIRD EDITION (1905)

vention of photography up to the end of the nineteenth century.
I undertook also to include in this work careful reproductions of
many incunabula and portraits of importance to the history of pho-
tography. The originals of most of these are fast disappearing and
have become very rare and difficult to obtain. They can now be found
in only a few places, particularly in Paris, London, and Vienna.
The collections of the Graphische Lehr- und Versuchsanstalt in Vien-
na, the Photographische Gesellschaft, and the Technical Institute in
Vienna contain highly valuable material, in part collected since 1839,
most of which has not yet been sufficiently studied and is quite un-
known in circles outside these institutions. I am greatly obliged to
the president of the Paris Photographic Society, the Paris Photo-
Club, the London Photographic Society, Major General J. Water-
house and Mr. George E. Brown, of London, Professor Vidal, M. J.
Demaria, and M. Davanne, of Paris, and Herr Braun, of Domach,
as well as to many other respected colleagues who have assisted me
and expedited my historical researches and investigations in a most
appreciative way.

Although I believe my Geschichte der Photographie to be the most
complete work of its kind thus far attempted, I realize that it cannot
be entirely exhaustive, since the space allotted to me does not suffice
for a broader treatment. The pursuit of too-minute detail, however,
would doubtless have affected my plan of presenting a general view
such as I have striven for in the treatment of the whole subject.

THE AUTHOR

Vienna
March, 1905

Preface to the Fourth Edition (1931)

The third edition of my Geschichte der Photographic (1905) has
been out of print for many years. It was impossible for me to accede to
the many requests for a new and enlarged edition during the confusion
of the War and the consequent interruption of international scientific
intercourse. Only within the past few years has it become possible for
me to gather and evaluate the foreign historical researches, which in
the meantime had greatly increased, and to incorporate them into my
earlier work after personal studies of their sources and origin. The pre-
vious edition of this work dealt with the history of photography only
to the end of the nineteenth century. The present new edition gives
the reader a complete survey of the history down to the end of the first
quarter of the twentieth century.

In the endeavor to present more than a narrow technical history of
photography, I have tried to record the development of photography
in relation to the events of the time and its application. In addition I
have taken great pains to hold fast to impartial, objective historical
statements, not permitting myself to be influenced by chauvinistic
tendencies, so that I might do full justice to the international history of
the advance of the science. The objectivity of my book is in no degree
diminished by the fact that as an old Austrian I have stressed the con-
tributions of my compatriots more generously than we find in other
works on this subject. The notable influence which Austrian workers
exerted on the development of photography during the earlier years
of its history amply justified my course. At that time Austria still was
the predominating great power in Europe; Vienna was acknowledged
as the guardian of the sciences and was held in high repute as a seat of
learning and patroness of arts. To record these facts is not only the
duty of historical truth and objectivity; it is the more justified because
all studies, particularly several of recent German origin, of the techni-
cal literature show lamentable gaps where the participation of Austrians
in the development of photography is concerned. At a time when the
tragic fate of my sorely tried Fatherland meets with so little under-
standing and sympathy in the world, it seems only right and just to give
a place to these important and outstanding contributions, which will
bear the scrutiny of the most searching historical inquiry, before the

X PREFACE TO THE FOURTH EDITION (1932)

memory of these early workers and their notable contribution to the
advance of photography are forgotten and sink into oblivion.

It seemed indispensable to an objective historical record of the sub-
ject that some account of the fortunes and personal experiences of the
pioneers in photography should be included, since these were often of
vital influence on the development of the art. As early as 1875 I had
begun to acquire, by active participation, a practical knowledge of
photography and the photomechanical processes. I also came into per-
sonal contact with many scientists and inventors, thus gaining an in-
sight into their ideals, purposes, and, often, the tragedies of their lives.
Through these contacts I obtained and fixed in my memory many
details of the history of the development of photography which
have great authentic value and deserve to be rescued from oblivion.
Hence, as far as possible I have followed my plan to delineate those
personages whom I thought important in the evolution of photog-
raphy and to give a record of their work in relation to their times
and background. This called for biographical data and portraits,
many of which were often difficult to obtain. Many notable workers
in that bygone period of the growth of photography ended their lives
misunderstood by their contemporaries, often in tragic circum-
stances, without having reaped the reward of their inventions. Their
lives and work, nevertheless, were not spent in vain. More fortunate,
gifted men of a later generation, coming from different callings,
have raised the art of photography to the high place it occupies today
in every sphere of human activity. However, all modem writers
have had to rely on and to build their works on the foundations pro-
vided by their predecessors.

It was also essential to the completeness of my work to consider
the many valuable historical papers which have appeared during
recent years in various foreign publications, even though these pre-
sented a purely national view, because despite this limitation they
contributed, in important details, to our knowledge of the history
of photography.

For instance: the history of photography in France is portrayed
by Georges Potonniee, in his Histoire de la decouverte de la photo-
graphie (Paris, 1925), in a manner worthy of recognition. Interest-
ing, however, as is this original study of the sources with regard to
the French claims, it can hardly be said to present an objective ex-
position of the collective international contributions to the domain

PREFACE TO THE FOURTH EDITION (1932) xi

of photography. I do not reproach M. Potonniee because he ignores
the German literature on this subject, presumably owing to his lack
of acquaintance with it, but his Histoire betrays a one-sided view,
even though he had German literary sources at his disposal. A per-
usal of the list of authors given in this work will show these points,
and criticism of them is recorded in their respective places.

The early history of photography was greatly advanced by val-
uable research documents contributed by Professor E. Stenger, of
Berlin, as well as by the publication of Wilhelm Dost’s Vorlaufer
der Photographie (Berlin, 1931).

I have received very generous and most welcome assistance in the
work of compilation and revision for this new edition of my history
from many sides. Thus, I am indebted to the Societe Fran^aise de
Photographie, Paris, for valuable information and communications
concerning French scholars; to the Royal Photographic Society of
Great Britain and its secretary, Mr. H. H. Blacklock; to the Eastman
Kodak Research Laboratory in Rochester, New York; to Herm
Regierungsrat Tippmann, the Oberstaats-Bibliothekar of the tech-
nical high school of Vienna; to the director of the Austrian Techni-
cal Museum of Trade and Industry, Vienna; to Herrn F. Paul Liese-
gang, Diisseldorf, Dr. Liippo-Cramer, Schweinfurt, Professor Leo-
pold Freund, University of Vienna; Hofrat Professor E. Valenta,
Vienna; Professor E. Stenger, Berlin; Dr. Helmer Backstrom, Stock-
holm, and Professor Y. Kamada, Tokio. To these gentlemen, to these
institutions, and to all the experts in the art who have aided and advanced
the achievement represented by this work— my heartiest thanks and
appreciation are here offered.

The presentation of the history of photography necessarily touches
so many departments of the technical arts and sciences that an extra-
ordinary variety of different but related subjects has been brought into
discussion. As a basis for the further study of the material and also to
make my books more useful to the reader and research student, I have
added a list of the authors and subjects. This was furnished by Herrn
Oberbaurat Fritz Schmidkunz, of Vienna, and deserves my sincere
appreciation.

My special thanks are due to the publisher, Wilhelm Knapp, Halle
a.S., who spared neither trouble nor expense in providing the best of
workmanship and material in the production of the books. The con-
siderable enlargement evident in this fourth edition of the Geschicbte

xii PREFACE TO THE FOURTH EDITION (1932)

der Fhotographie made it desirable to issue the work in two parts in
order to facilitate the binding in two volumes. In each part of the Halle
1932 edition is found a list of contents and illustrations; a complete index
to authors and subjects is at the end of the second volume.

J. M. Eder

Vienna

November, 1931

Translator’s Preface

It was in 1932 in Dr. Eder’s beautiful villa at Kitzbiihel in the Austrian
Tyrol that at his request I promised to translate his work Geschichte
der Photographie (4th ed., 1932) for the benefit of the English-speak-
ing student of the subject. The demands of the German publishing
house and the changed political conditions in Germany which followed
put a stop to the chance of publication at that time. Notwithstanding
its seeming Chauvinism, the work is unique, and it is a monument to Dr.
Eder’s long years of study and an eloquent witness to his accomplish-
ments.

The illustrations appearing in the German work are omitted since
most of them have only an ornamental value and are of little practical
use to the student.

My original translation was edited by Mr. John A. Tennant, of New
York City. The typescripts were read and edited by Mr. George E.
Brown, of London, for twenty-nine years editor of the British Journal
of Photography ; by Mr. William Gamble, editor of Penrose's Annual,
London; by M. Louis-Philippe Clerc, of Paris; and by Dr. Eder, who
furnished me with additional notes. Any deviations from the origi-
nal text are due to him or to these collaborators. I am also indebted
for kind assistance to Dr. C. E. Kenneth Mees and Dr. Walter Clark, of
the Eastman Kodak Co., and to Dr. Fritz Wentzel, of Ansco Co., for
English translations of some of the German photochemical terms. The
final reading of the text was done by Mr. Charles M. Adams, Assistant
to the Director of Libraries, Columbia University.

Any profit resulting from this publication will be paid by the pub-
lishers to the Columbia University Libraries of New York City.

I apologize in advance for whatever errors and omissions may appear
in my translation and can only plead in extenuation, ut desint vires,
tamen est laudanda voluntas.

Edward Epstean
hon. f. r. p. s.

New York City
January 2, 1945

xiii

Contents

I. From Aristotle (Fourth Century before Christ) to the Al-
chemists i

II. Influence of Light on Purple Dyeing by the Ancients 8

III. Thought and Teaching of the Alchemists 1 5

IV. Experiments with Nature-Printing in the Sixteenth and

Seventeenth Centuries 33

V. The History of the Camera Obscura 36

VI. Stereoscopic (Binocular) Vision 45

VII. The Invention of Projection Apparatus in the Seventeenth

Century 46

VII. (Rewritten). The Invention of Projection Apparatus 5 1

VIII. Studies of Photochemistry by Investigators of the Seven-
teenth Century up to Bestuscheff’s Discovery in 1725 of the

Sensitivity of Iron Salts to the Light and the Retrogression of

Processes in Darkness 55

IX. Phenomena of Phosphorescence: Luminous Stone; Dis-

covery of the Light-Sensitivity of Silver Salt; the First Photo-
graphic Printing Process by Schulze, 1727 57

X. The Life of Johann Heinrich Schulze 64

XI. Photochemical Research in the Eighteenth Century until
Beccarius and Bonzius (1757), T ogether with a Digression on

the Knowledge at That Time of the Instability of Colors 8 3

XII. From “Giphantie” (1761) to Scheele (1777) 89

XIII. From Priestley ( 1 7 7 7 ) to Senebier ( 1 7 8 2 ) ; T ogether with

an Excursion into the Application Made in Those Days of
Light-Sensitive Compounds to Magic Arts 99

XIV. From Scopoli (1783) to Rumford (1798) 107

XVI

CONTENTS

XV. From Vauquelin ( 1 798) to Davy ( 1 802) 1 19

XVI. The Studies of Sage (1803), Link, and Heinrich on the

Nature of Light (1804-8) up to Gay-Lussac and Thenard
(1810) 142

XVII. From the Discovery of Photography in Natural Colors

by Seebeck (1810) to the Publication of Daguerre’s Process
(1839) 153

XVIII. Special Investigations into the Action of Light on Dye-
stuffs and Organic Compounds (1824-35) 186

XIX. Joseph Nicephore Niepce 193

XX. Relationship between Niepce and Daguerre 207

XXI. The Life of Daguerre 209

XXII. The Agreement between Nicephore Niepce and Da-
guerre (1829) 215

XXIII. Daguerre Discovers the Light-Sensitivity of Iodized

Silvered Plates 22 3

XXIV. Joseph Nicephore Niepce’s Death in 1833; His Son Isi-

dore Takes His Father’s Place in the Contract of 1829 with
Daguerre; Daguerre Discovers Development with Mercury
Vapors 226

XXV. Daguerre and Isidore Niepce Attempt Unsuccessfully in
1837 to Sell Daguerreotypy by Subscription; They Offer
Their Invention to the Government; Arago’s Report to the
Academy on January 7, 1839; Agreement Arrived at June 1 4,

1839 230

XXVI. Bill for the Purchase o f the Invention of Daguerreotypy
by the French Government, Which Donates It to the World

at Large 232

XXVII. Daguerre’s Activities after the Publication of Daguer-
reotypy; Report on Daguerreotypy to the Emperor of Austria 246

CONTENTS

xvu

XXVIII. Success of Daguerreotypy and Its Conunercial Use;

the First Daguerreotype Cameras, 1839 248

XXIX. Commercialization of Daguerreotypy; Description of

the Process 250

XXX. First Use of the Word “Photography,” March 14, 1839 258

XXXI. Scientific Investigation o f the Chemico-physical Basis of

Photography 2 59

XXXII. The First Daguerreotype Portraits; Exposures Re-
duced to Seconds 271

XXXIII. The Daguerreotype Process in Practice 279

XXXIV. Petzval’s Portrait Lens and the Orthoscope 289

XXXV. Daguerreotypy as a Profession, 1840-60 313

XXXVI. Colored Daguerreotypes 3 1 5

XXXVII. Invention of Photography with Negatives and Posi-
tives on Paper and Its Practical Development by Talbot 316

XXXVIII. Reaction of the Invention of the Daguerreotype,
the Talbotype, and the Earlier Photomechanical Processes on
the Modern Processes of the Graphic Arts 3 3 1

XXXIX. Bayard’s Direct Paper Positives in the Camera and An-
alogous Methods 334

XL. Reflectography (Breyerotypy) by Albrecht Breyer, 1839 336

XLI. Photographic Negatives on Glass (Niepceotypes) 338

XLII. The Wet Collodion Process 342

XLIII. Beginning of Photography as an Art by Daguerreotypy,

Calotypy, and the Wet Collodion Process 348

XLIV. Portable Darkrooms; Theory and Practice of the Wet

Collodion Process 357

XLV. Direct Collodion Positives in the Camera 369

XL VI. Chemical Sensitizers for Silver Halides 371

XV111

CONTENTS

XL VII. The Dry Collodion Process and the Invention of Alka-
line Development 372

XL VIII. Invention of Collodion Emulsion 376

XLIX. Invention of Collodion Layers for the Production of

Stripping Films on Spools 380

L. Stereoscopic Photography 381

LI. Microphotography 385

LII. Photomicrography and Projection 388

LIII. The Solar Camera 391

LIV. Balloon Photography 393

LV. Photogrammetry 398

LVI. Modem Photographic Optics 403

LVII. Further Development of Photochemistry and Photo-
graphic Photometry 4 1 2

LVIII. Photoelectric Properties of Selenium 420

LIX. Gelatine Silver Bromide 42 1

LX. Gradual Increase of Sensitivity of Photographic Processes

from 1827 until the Present Time 439

LXI. Gelatine Silver Bromide Paper for Prints and Enlarge-
ments 439

LXII. The Discovery of Gelatino-Silver Chloride for Trans-
parencies and Positive Paper Images by Chemical Develop-
ment (1881); Artificial Light Papers 443

LXIII. Calculation of Exposure, Determination of Photograph-
ic Speeds, Sensitometry, and the Laws Governing Density 449

LXIV. Discovery of Color-Sensitizing of Photographic Emul-
sions in 1 873; Professor H. W. Vogel Discovers Optical Sen-
sitizing 457

LXV. Discovery of Desensitizing 478

CONTENTS

xix

LXVI. Film Photography and the Rapid Growth of Amateur

Photography 485

LXVII. The Stroboscope and Other Early Devices Showing

the Illusion of Movement in Pictures 495

LX VIII. Eadweard Muybridge’s Motion Picture Photography 501

LXIX. Photographic Analysis of Movement by Janssen and

Marey 506

LXX. Ottomar Anschutz Records Movement by Instantaneous

Photography and Invents the Electro tachyscope (1887) 512

LXXI. Development of Cinematography 514

LXXII. Photographing Projectiles in Flight and Air Eddies 524

LXXIII. Artificial Light in Photography 528

LXXIV. Printing-out Processes with Silver Salts 534

LXXV. Mordant-Dye Images on a Silver Base; Uvachromy and

Allied Processes 539

LXXVI. Printing Methods with Iron Salts; Photographic Trac-
ing Method (Blue Prints, etc.) ; Platinotype 542

LXX VII. Fotol Printing (1905) and Printing Photographic
Tracings [(Blueprints, Brown Prints, and Others] on Litho-
graphic Presses (1909) 549

LXXVIII. Photographic Printing Methods with Light-Sensi-
tive Diazo Compounds: Diazotypy, Primuline Process, Ozalid
Paper 550

LXXIX. Discovery of the Photographic Processes with Chro-
mates by Ponton (1839), and of the Light-Sensitivity of
Chromated Gelatine by Talbot (1852) 552

LXXX. Gum Pigment Method 560

LXXXI. Pigment Images by Contact; Marion (1873); Manly’s
Ozotype (1898); Ozobrome Process (1905); Carbro Prints 561

LXXXII. Oil Printing 562

CONTENTS

LXXXIII. Bromoil Process 564

LXXXIV. Photoceramics, Enamel Pictures with Collodion,
and Dusting-on Methods 566

LXXXV. Electrotypes; Auer’s Nature Prints 568

LXXXVI. Electrotypes and Galvanic Etchings 574

LXXXVII. Photogravure with Etched or Galvanically Treated

Daguerreotype Plates 577

LXXXVIII. Invention of Photoelectrotypes for Copperplate
Printing and Typographic Reproduction 581

LXXXIX. Production of Heliogravures by Means of the As-
phaltum Method; Beginning of Halftone Steel Etching 591

XC. Heliographic Steel and Copper Etching with the Chro-
mated Glue Process; Klic’s Photogravure; Printing with the
Doctor; Rotogravure 593

XCI. Photolithography; Zincography; Algraphy 608

XCII. Collotype 6 1 7

XCIII. Photographic Etching on Metal for Typographic Print-
ing, Zincography, Copper Etching, and the Halftone Process 62 1

XCIV. Three-Color Photography 639

XCV. Photochromy; Color Photography with Silver Photo-
chloride; Lippmann’s Interference Method and “Photo-
graphic Integrale”; Kodacolor; Bleaching-out Process 664

XCVI. Photographic Technical Journals, Societies, and Educa-
tional Institutions 676

XCVII. Supplement to the Chapters on Daguerreotypy and

Cinematography 7 1 7

Biography of Josef Maria Eder, by Hinricus Liippo-Cramer 720

Notes 729

Index 8 1 9

Chapter I. from aristotle (fourth cen-
tury BEFORE CHRIST) TO THE ALCHEMISTS

Light, which makes all things visible, this common and blessed prop-
erty bestowed on all beings of the universe, has such an important ob-
ject and place in nature that its character and qualities have not escaped
studious investigation by the most gifted and ingenious nation of
antiquity. We are indebted to the Greeks not only for the discovery
of those laws which light observes when in motion through homo-
geneous and heterogeneous media and when reflected by polished
surfaces; but they alone of all ancient people realized, from the na-
ture of these laws, that optics is a mathematical discipline. They were
also the first to attempt to bring within the domain of mathematics
that infinitely subtile nature of light which appears to our senses so
nonmaterial. [Translator’s note: To my mind the shortest and most
satisfying definition of light is that of the physicist, namely, light is
that form of energy (radiant energy) which, acting on the organs
of sight, makes visible the object from which it proceeds.]

Instructive in this respect is E. Wiedemann’s Geschichte der Lehre
vom Sehen. 1 According to Wiedemann, there were two main schools
of thought among the Greeks regarding the nature of vision. One,
represented by Plato (42 7? -347? b.c.), held that sensitive threadlike
rays are emitted from the eye and that the objects perceived are
touched by these rays. The other school, led by Aristotle (384-322
b.c.) and Democritus (d. 370 b.c.), taught that the objects themselves
emitted the light rays which meet the eye. Avicenna (a.d. 980-
1037) offered as a compromise the theory that light rays emitted
from the eye function as organs of vision after they have united
with the luminous air. As is well known, the opinion of Aristotle
prevailed; Euclid (fl. c. 300 b.c.) and Ptolemy (fl. a.d. i 27-141)
accepted it.

The generally accepted view, until recently to be found in various
histories of physics, is that Ibn al Haitam (A 1 Husen, d. 1038) was
the first to revive the correct view of Aristotle. As a matter of fact,
this Arabian savant discussed and firmly established the theory that
vision is created by the agency of light rays. Ibn al Haitam, however,
had predecessors and contemporaries who were of the same mind.

FROM ARISTOTLE TO THE ALCHEMISTS

These were the Arabian philosophers and physicians who supported
the Aristotelian theory and as medical men were led to the correct
solution of the problem.

According to the “Lautere Briider” (Ichwan A 1 Safa, tenth cen-
tury), light emanates from the body, penetrates and is absorbed in
part by the transparent matter or the permeable substance of the
object, the unabsorbed light rays conveying the color of the object
by reflection to the eye. The other theory, that rays are projected
from the eye, was rejected as folly.

When convenient, however, the Arabs referred to rays that pro-
ceed from the eye— for instance, Ibn al Haitam, who, as he tells us,
follows Ptolemy in his writings concerning the configuration of the
universe.

Moreover, Averroes (Ibn Ruschd, 1126-98) states quite appro-
priately in his commentary on the meteorology of Aristotle (Lib. hi,
cap. n) : “Since one arrives at the sameresultin the study of perspective,
one may accept either view; but as writings concerning the soul demon-
strate that vision is not produced by rays proceeding from the eye, it
is more fitting to adopt this last (i.e., the correct) theory” ( Jahrbuch f.
Phot., 1893, p. 318).

The knowledge o f convex lenses and spectacles is also related to the
theory of vision. Convex lenses were well known to the ancients,
examples of quartz crystal or glass lenses having been found at Nineveh,
Pompeii, and elsewhere. It is supposed that they were used as magnifiers
or burning glasses, as is indicated in the writings of Pliny and Seneca.
A quartz crystal found at Tyre and preserved at Athens, at first thought
to be a magnifier or eyeglass, was probably nothing more than a knob or
button. The emerald through which, according to Pliny, the Emperor
Nero viewed the gladiatorial combats, was not used as a spectacle or
device to aid vision, but undoubtedly (contrary to the oft-quoted opin-
ion) as protection against the glare of sunlight. This view is accepted
by E. Bock, for various reasons. The first indisputable mention of spec-
tacles is presented by Roger Bacon in 1 2 76 (Emil Bock, Die Brille und
ihreGeschichte, 1903; Emil Wilde, Geschichte der Optik, 1838, p. 92) .

The development of the theory of vision and the history of the de-
velopment of geometrical optics, so admirably dealt with by Wilde in
his history above mentioned , 2 will not be further considered here, be-
cause I desire to emphasize the early concepts of the Greek philosophers
as to the action of light on matter (organic substances) .

FROM ARISTOTLE TO THE ALCHEMISTS

The theories of Plato, Epicurus, and Hipparchus concerning light
and vision postulated that vision is produced by the emanation of image-
bearing light rays from the eyes, analogous to the sense of touch; that
light emanates from the eye as from a lantern. These propositions,
obviously, were unfavorable to any discovery of facts leading to the
realm of photochemistry.

The Greek philosopher Empedocles (483-424 b.c.) defined light as
matter (corpuscles), but this was later contradicted by Aristotle, who
held that light and color were not bodily emanations from luminous
objects and explained vision as a motion of the transparent medium
existing between the eye and the visible object.

There can be no doubt that Aristotle concerned himself more than
did any other philosopher of the ancient world with the intimate study
of the nature of light. His teaching as to the transmission of light has
been affirmed in modern times. How far he was in advance of his time in
the difficult field of optics (light, vision, and color) is evident from the
fact that even today, with our highly developed technique, his teachings
dealing with light still attract admirers and followers.

Aristotle sets forth his researches dealing with light in three tracts—
“On Light,” “On the Senses,” and “On Colors”— of which the last
named is the most important for us. This treatise “On Colors” is some-
times attributed to Theophrastus, 3 a pupil of Aristotle, or to the peri-
patetic school, but it is the decision of those who rely on the judgment
of Plutarch 4 that it was unquestionably the work of Aristotle.

It may be taken for granted that the earliest observations of the in-
fluence of sunlight in affecting a change of matter (changes in organic
substances) were made on plants. Knowledge of the fact that sunlight
is necessary to the formation of the green coloring matter of plants is
probably as old as the human race.

Aristotle indicates his view on this matter in various parts of his writ-
ings. He expresses himself very clearly in his book “On Colors,” chap.v,
as follows:

Those parts of plants, however, in which the moisture is not mixed with
the rays of the sun, remain white .... Therefore all parts of plants which
stand above ground are at first green, while stalk, root, and shoots are white.
Just as soon as they are bared of earth, everything turns green .... Those
parts of fruit, however, which are exposed to sun and heat become strongly
colored.” 5

FROM ARISTOTLE TO THE ALCHEMISTS

He was also familiar with the action of light on the coloring of the
human skin. To be sure, he goes too far when he attributes the blackness
of the Negro to the intensity of sunlight. His view is, however, original,
as is shown by comparison with Herodotus (484-425 b.c.), who, as is
well known, accepted the explanation that “the black emanations of
the body” of the Ethiopian are responsible for his color, while Onesi-
critus, much later, inclined to the opinion that the black color is the
result of hot rain water falling from the skies. 6

EARLY ANTICIPATIONS OF THE EFFECT
OF LIGHT ACTION

A closer search among the writings of the ancients brings to light
many anticipations of modern thought and theory, as Gaea (1908,
p. 1 25), the popular German scientific journal explains. For example,
Sophocles (495-406 b.c.) mentions in his poem “Trachinierinnen”
a light-sensitive substance which required the employment of a dark
room (verse 69 1 ) and was to be kept away from sunlight in a light-
proof box (verse 692). Dejanira prepared from Nessos’ blood a love
philter for her husband Hercules, by anointing a woolen undershirt.
She was instructed by the dying centaur to make her preparations in
the dark, fold the garment, and place it carefully in a chest. She cast
aside carelessly, however, some of the wool left over. As soon as these
were struck by the rays of the sun, they disintegrated into a mass of
flakes and emitted fumes.

The author asked Dr. Edmund Hauler, professor of classic phi-
lology at the University of Vienna, for more detailed information.
He replied that in the above note the situation is in general correctly
reproduced. In verse 555 of the “Trachinierinnen” we find an address
by Dejanira to the chorus: “I had of old a gift given by the centaur,
before this time kept secret in a brazen kettle, which I received once
on a time while yet a girl from shaggy Nessos, when he was stricken
to death.”

According to his instructions, Dejanira used the blood of Nessos,
poisoned by dragon’s blood in which Hercules had dipped the deadly
arrow which he had sent to Nessos. She had preserved the tincture
carefully away from the fire and kept it always untouched by sunlight,
deep in the recesses of the house, until her jealousy was aroused by
Hercules, when she anointed an undergarment with it and sent it as
a pretended love gift. Sophocles tells it as follows:

FROM ARISTOTLE TO THE ALCHEMISTS

I smeared it in the house at home secretly with wool, having plucked the
fleece from a lamb of our own herd, and, folding up the gift, I laid it un-
touched by the sunlight, in a hollow chest, as you saw. But coming in I see
something which is puzzling to hear, unintelligible for a man to understand:
For I happened to throw the tufts of wool from the lamb, with which I
had done the rubbing into the blaze of the hot rays of the sun. But as they
grew warm the whole mass dissolved, so as to be unrecognizable, and crum-
bled away on the ground, in appearance most like when one sees sawdust
while wood is being cut; so it lies there crumbled away. But out of the
earth where it lay, bubbles of foam sizzle up in masses, as when one pours
the rich drink of the vintage upon the earth from Bacchus’s vine.

The “magic” effect of the poisonous love philter manifested itself
in the crumbling of the fabric and the hissing noise of the vapors which
issued from it on exposure to sunlight, but especially in the terrible
tortures endured by Hercules when the poisoned garment touched
his warm body.

The narrative is so realistic that one cannot but feel that Sophocles
knew something of the destructive effect of sunlight on wool. It is, how-
ever, useless to indulge in further speculation in this, since the descrip-
tion is simply a creation of the poet’s fancy.

It is easier to connect the fancies of the Roman poet Publius Papinius
Statius (a.d. 40-96) with photography, in anticipation of the daguerreo-
type process.

Statius was a contemporary of the emperors Vespasian and Domitian
and a favorite of the latter. Among his fanciful poems still extant is a
collection under the title “Silvae,” and in iii. 4, of the collection we find
a poem entitled “The Hair of Earinus.” The Frankfurter Nachrichten
in 1928 reported that this poem mentions an image formed by light on
a mirror of gold. I quote from the report: “The youth Earinus, of Per-
gamus, in Asia Minor, was a great favorite of the Emperor Domitian.
It is reported that his image, by magic, was permanently fixed on a small
silver plate, 7 into which he had gazed for a period of time. His counter-
part, Statius continues, was fixed merely by placing himself opposite—
an image fixed on a silver plate. The picture was made on the seven-
teenth birthday of Earinus, when, according to custom, he was dedi-
cated to one of the gods by having his locks cut off. Both the image fixed
on the small silver mirror and the locks traveled to the Temple of Aes-
culapius at Pergamus.”

Again the author consulted Professor Edmund Hauler, of Vienna, in

6 FROM ARISTOTLE TO THE ALCHEMISTS

order to obtain more details of the quotation by reference to the origi-
nal text in Statius: “Silvae,” (iii. 4, Capilli Flavi Earini) .

Tunc puer e turba, manibus qui forte supinis
nobile gemmato speculum portaverat auro:

“Hoc quoque demus,” ait, “patriis nec gratius ullum
munus erit templis ipsoque potentius auro;
tu modo fige aciem et vultus hue usque relinque.”

Sic ait et speculum reclusit imagine rapta.

These Latin verses may be rendered in English as follows:

Then a boy from the throng, who, it chanced, had brought on his upturned
hands a splendid mirror of gold studded with jewels, said: “This also let us
give to the temples of our fathers; no gift will be more pleasing, and it will
be more powerful than gold itself. Do you only fix your glance upon it and
leave your features here.” Thus he spoke and showed the mirror with the
image caught therein.

There is no mention of a silver plate, but gold is twice spoken of as the
material. The mirror is described as having the form of a shield and was
probably a hand mirror; at that time such mirrors were often embel-
lished with a pictorial representation. The poet probably thought that
Cupid, by his divine power, had quickly engraved a portrait of Earinus
on the surface of the mirror as he gazed on it. Professor Hauler adds:
“It is to be noted that this quotation is referred to by Henry in the
Neuen JahrbiicbernfiirklassischePhilologie (i 863,XCIII, 643) as an-
ticipating Daguerre’s invention.”

The picture of Earinus, formed by light, a bold dream of classical
poetry, touches the imagination of today as a prophecy.

KNOWLEDGE OF THE ANCIENTS CONCERNING
THE ACTION OF LIGHT ON MATTER

Two thousand years ago the destructive effect of light on certain
colors used in painting, especially on cinnabar, was well known. Vi-
truvius (first century b.c.), a celebrated Roman architect under both
Caesar and Augustus, writes in his “De architectura” (vii.9), the only
work of this kind which has come down to us from antiquity, about
cinnabar (minium): “When used for trimming draperies in rooms not
open to sunlight, it will keep its color unchanged; but in public places
(peristyles, auditoriums), and in similar places where the light of sun
and moon has access, it spoils immediately when exposed to their rays

FROM ARISTOTLE TO THE ALCHEMISTS

and the color loses its vividness and brilliancy, turning black.” Another
writer, Faberius, who desired to decorate his house on the Aventine,
had a similar experience. He covered the walls of the peristyle with cin-
nabar, but after four weeks they were so unsightly and spotty that he
had to cover them with another color. However, if one wishes to bestow
more care on the coating of cinnabar, in order to render it permanent,
this may be done by first allowing the painted wall to dry and then, us-
ing a bristle paint brush, covering the wall with a mixture of molten
Punic wax and oil, known to the Greeks as “kausis.” This wax coating
permits no penetration by the rays of sun or moon. Vitruvius (vi. 7) dis-
cusses in detail the question toward which point of the compass a
building should be erected and remarks that picture galleries, textile
workrooms (plumariorum textriniae), and the studios of painters
should face northward, in order that the colors used in such places
should remain unchanged.

It is very doubtful whether Pliny (first century a.d.) intended, as
many authors report, to refer to the darkening of silver chloride in
light when he states that “silver changes its color in mineral waters as
well as by salt air, as, for instance on the Mediterranean shores of Spain”
( Historiae naturalis xxxiii. 55, 3 ) . I believe this reaction was undoubted-
ly assisted by the presence of hydrogen sulphide. Elsewhere (xxxvii. 1 8 )
he says: “It is curious to note that many emeralds deteriorate in time;
they lose their green color and suffer a change under sunlight.” On the
other hand, a knowledge of the change of colors by light is clearly
indicated in the following quotation from Pliny (xxxiii. 40): “The
effect of the sun and moon on a coat of minium (cinnabar?) 8 is inju-
rious.” This statement is copied almost verbatim from the work of
Vitruvius. Similarly, in his statement about the wax covering as preven-
tive of destructive light action, Pliny (xxi.49) closely follows Vitruvius.
He speaks of bleaching wax “in the open air by the light of sun and
moon” and discusses those methods of encaustic painting which use
wax melted by heat and applied with the paint brush: “a method of
painting which, when applied to ships, does not suffer the least change
from sun, salt water or the weather” (xxxv. 41).

No further statements about the change of other colors are to be
found in the early accounts, which is perhaps explained by the fact
that they made little use of colors other than red. According to Pliny
xxxii. 7, 1 17), red paint was for long the only color employed in the
execution of old pictures called monochromata, and it was especially

8 INFLUENCE OF LIGHT ON PURPLE DYEING

minium (Pbj, O4, red lead oxide) and rotel (mixture of ferrous oxide)
which were used. Even at a later period, when the primitive method of
painting had been abandoned, the use of luminous colors, red and yel-
low, still predominated, though now painters employed four colors, as
Pliny relates (xxxv. 7, 50) : white, black, red, and atticum, a color simi-
lar to ocher. 0 Dioscorides describes, in chap, xxxii of the first book of his
work De materia medica, the process of bleaching oil of turpentine:
“Take some of the lighter kind, place it in the sun in an earthen vessel,
mix and stir it violently until scum is formed, whereupon add resins and,
if necessary, expose it again to the sun.

However, new researches have been made respecting the colors used
by the ancient Romans; the material for these researches was found at
Pompeii. 10 Their constituent parts were mostly yellow and red ocher,
vermilion, minium, massicot (lead oxide), mountain green (basic cop-
per carbonate), some kind of smalt, carbon, and oxide of manganese.
Of all these colors, cinnabar was, perhaps, particularly suited to demon-
strate a change in color when exposed to light. It is not easy to under-
stand why these writers failed to investigate and record further their
observations of the changes in dragon’s blood and indigo blue, which
colors, however little used, were undoubtedly known at that time.

Chapter II. influence of light on purple

DYEING BY THE ANCIENTS

The early writings and observations concerning purple dyeing deal
chiefly with the photochemical properties of light to effect changes in
or decompose colors. The ability of light to produce dyes was recog-
nized then only in the case of the green coloring matter of plants. But
occasionally during the early practice of purple dyeing it was noticed
that light possessed the remarkable quality of not only influencing and
originating beautiful colors but also enriching their vividness of hue. 1

The purple of the ancients was the most beautiful and costly dye of
antiquity. The snails ( purpura ) which yielded the dye used in purple
dyeing were found on the coast of the Mediterranean, but the beauty
and durability of the color varied greatly with the place of their origin
and with their quality. The red and violet varieties of purple produced
at Tyre won world-wide renown and were well known as early as the

INFLUENCE OF LIGHT ON PURPLE DYEING

time of Moses. The two species of snails most favored by the ancients
were Murex hrandaris and Mur ex trunculus. Their glands secrete a
yellow, pus-like mucus, which develops under the influence of sunlight
into a purple-red or violet dye.

For centuries the Phoenicians alone possessed the secret of the man-
ufacture of purple. The coloring matter manufactured from these snails
quickly gained general favor, and purple garments were esteemed a
mark of distinction for rulers and high dignitaries. The use of purple
garments increased with the wealth of nations, notwithstanding the
extremely high price which was demanded for clothes of this sort. The
Roman emperors transferred the manufacture of purple to Italy and
conducted it as a monoply. The art of purple dyeing, which, like many
other arts, had reached a high level at this time, was lost almost com-
pletely in the stormy period which marked the migration of nations.
Fora short time the art was still preserved in the Byzantine Empire, only
to become extinct even there in the twelfth century. Important im-
perial decrees were written in purple ink, and today one may still find
valuable manuscripts, written on purple-colored parchments in the
libraries at Upsala and Vienna. The latter has in its possession two such
examples of religious manuscripts.

A noteworthy piece of silk, dyed in antique purple, is found in the
state robe produced for the Saracen court at Palermo, in Sicily, which
after curious vicissitudes became the coronation robe of the German
emperors. It is now preserved among the exhibits of the former imperial
jewel room in Vienna. Incidentally, it is well to record that the hue
of purple was never bright red, but showed rather a violet shade, and
there are numerous examples of shades running toward the blue.

The purple dyeing process deserves much consideration in the his-
tory of photochemistry. Sunlight plays a great role in the manufacture
of these beautiful purple-dyed materials, because they are made pos-
sible only through the effect of sun rays on the light-sensitive secretion
of the Purpura snail. Although many early authors have much to say
about Purpura snails and purple dyeing, the references made by Greek
and Latin writers are scattered; they treat them only as of secondary
importance. Only rarely do they refer to the necessity of the presence
of sunlight in the creation of the splendor and radiance of colors. The
fundamental investigation of this subject was reserved for Alexander
Dedekind, formerly director of the Egyptian Department of the Im-
perial Museum of the History of Art, Vienna, whose research clarified

10 INFLUENCE OF LIGHT ON PURPLE DYEING

the history of the subject. Dedekind is the outstanding authority on the
subject of purple, and his works form the basis of our knowledge
(Dedekind, Ein Beitrag zur Purpurkunde, Berlin, Verlag von Mayer
und Muller, Bd. I, 1898; Bd. II, 1906; Bd. Ill, 1908).

The oldest accounts, as Dedekind proves, are those of Aristotle, who
relates, in his work on colors, the advantageous influence of light in
purple dyeing. Julius Pollux (latter half of the second century a.d.)
writes in a similar manner in his dictionary Onomasticon, and Philostra-
tos, a Greek Sophist from Lemnos, who lived in Rome about the middle
of the third century a.d., writes in his book Imagines: “The purple
of Tyre looks dark and derives its beauty from the sun, which gives it
the shade of a pomegranate blossom.”

Until very modem times priority for the recognition of the influence
of light in purple dyeing was attributed, in ignorance of the ancient
authors, to the celebrated Eudoxia Macrembolitissa, because of an old
historic-mythological dictionary, called “Ionia,” an interesting Greek
manuscript which it is alleged was reported as composed by her. Until
quite lately this manuscript was said to be dated about the eleventh
century. It is preserved in a library at Paris, and in it the alleged Eudoxia
describes how the material to be dyed is dipped into the purple dye.
She continues: “The purple color becomes first class only if the material
is exposed to the sun, because the rays of the sun add great fire which
darkens the color, and the brilliancy is brought to its greatest perfection
by the fire from above.”

Bischoff, in his Versuche einer Geschichte der E'drbekunst (1780,
p. 1 9) , was the first to call attention to this clear and explicit description
of the part played by light in the formation of purple colors. 2 The
citation quoted in the third edition of the author’s book was taken from
the work by Bischoff. The book with which Eudoxia is credited, en-
titled “Ionia,” was published by Villoison in the first volume of the
Anecdota Graeca (1781), where on pages 53-58 the purple snail is
described (new edition by Flach, Leipzig, 1850).

Eudoxia was the daughter of a respected Byzantinian, who during
the reign of Emperor Michael IV, the Paphlagonian, occupied an
important official position in Byzantium. She was famous for her beau-
ty, erudition, and Hellenic culture. She became the second wife of
Constantin Ducas, who later ascended the throne of Byzantium ( 1059)
as Constantin X. He appointed her Regent, and she reigned alone after
his death (1067) for a time, then married General Romanos, who was

INFLUENCE OF LIGHT ON PURPLE DYEING 1 1

captured in the war with the Seldshooks, a Turkish tribe, and after
being set free, was persecuted by his own people. These internal strug-
gles over the sovereignty ended when her brother-in-law Johs. Ducas
had her arrested and imprisoned as a nun in the Convent of St. Mary on
the Bosphorus, which she herself had built. The gifted empress, who
now devoted all her time to the pursuit of learned studies, lived for
twenty-five years after being dethroned. Therefore it is quite plausible
that the manuscript which has been ascribed to her, entitled “Ionia”
or “Violarium” (Garden of Violets), may have originated with her.
The authorship of this book, although conceded to Eudoxia by many
until quite recent times, 3 is absolutely denied to her by modern critics.

According to Karl Krumbacher this work is to be ascribed, 'not to
Eudoxia, but to the Greek Constantin Palaeokappa, who recompiled
it from different sources. The authenticity of “Ionia” as the work of
Eudoxia was passionately defended by Flach, but in a vain controversy,
and according to Dedekind there remains no doubt that “Ionia” did
not originate with the purple-born Eudoxia.

Krumbacher 4 also declares it to be apocryphal and concludes that
very likely it was put together by the Greek Constantin Palaeokappa
from various sources. Almost half the work is copied from a book by
Phavarinus (a Latin author of the times of Hadrian, second century
a.d.), and printed at Basel in 1538; the Greek writer also made use of
the Basel edition of Palaephatos and Cornutus of 1543. The principal
statements dealing with the spuriousness of Eudoxia’s claim originate
from Pulch (“Die Pariser Handschriften des Honnus Abbas und Eu-
doxia,” Philologus, 1882, pp. 341, 346, and his treatise Konstantin Palae-
okappa). Pulch was also the author of Jonia der Eudokia (Hermes,
1882, pp. 177, 192). Also see the discussion by Wilamowitz-Mollendorf
in Die deutsche Liter aturzeitung (1880, p. 228, and 1881, p. 319).
Flach replied to this with a pamphlet which is not convincing: Herr
Wilamowitz-Mollendorf und Eudokia; eine Skizze aus dem byzan-
tinischen Gelehrtenleben, added to the second part of Jahn’s Jabrbucb
(1881).

Whoever may be the author of the book “Ionia,” it is without doubt
the most lucid and important of early contributions to our knowledge of
the photochemical change of colors in the dyeing with purple.

It was not until the seventeenth century that further research added
to our knowledge of purple snails. Here we are indebted to William
Cole, of Minehead, England, who discovered on the shores of Somer-

i2 INFLUENCE OF LIGHT ON PURPLE DYEING

setshire and South Wales shellfish ( Buccinum ) containing purple. He
observed that their juice, when spread on linen or silk, produced first
a greenish color, which changed rapidly to dark green and light purple,
which turned in a few hours under bright skies to a deep purplish red.
Cole discovered also that every one of these shades of color remained
fixed when the dyed material was kept in a dark room. He also noted
an odor of garlic during the decomposition of the juice while exposed
to sunlight. In November, 1684, Cole sent some samples of such dyed
linen material to the Royal Society of London, with a description of his
experiments.®

In the beginning of the eighteenth century the celebrated French
scholar of natural sciences and inventor of the thermometer which is
named after him, Rene Antoine Ferchault de Reaumur (1683-1757),
occupied himself with the study of the purple snails. Several of his
important works deal with the domain of zoology. He studied especially
the life of insects and Crustacea, investigating the formation of the
shells of this species.

Reaumur found a great many Buccina on the coast of Poitou and pub-
lished in 1 7 1 1 , in his treatise Sur une nouvelle pourpre, his observations
of the important part which light plays in the formation of red color. 8
He observed that the animal secretion when fresh was yellowish and
turned violet only when exposed to the sun and finally to purplish red.
The air alone did not affect the color in the dark, nor did the light
emanating from a hot fire prove effective in the process of turning the
color red, although the fire was much hotter than sunlight. However,
when sunlight was concentrated on it through a burning glass, the
reddening was greatly accelerated. His experiments led him to the
conclusion that “in order to produce the same changes in the juice
which can be affected by the warmth of sunlight, it is necessary to
employ a much higher degree of heat in the fire.”

These studies by Reaumur inspired, in 1736, General Inspector of
the Marine and French Academician Duhamel du Monceau (1700-
1782) to new experiments with the purple dye indigenous to certain
shellfish. 7 In his dissertation Quelques experiences sur la liqueur colo-
rante que fournit le pourpre, espece de coquille qu'on trouve abondam-
vient sur les cotes de Provence 8 he describes, in much the same manner
as did his predecessors, a similar change in color (reddening) which
takes place when the white secretion of certain mollusks is exposed to
sunlight. He satisfied himself that dark heat does not effect a change of

INFLUENCE OF LIGHT ON PURPLE DYEING

color, that fire does so only to a very small degree , 9 while sunlight in a
few minutes changes the color of the secretion or that of linen dipped in
purple. Reddening by light took place also when the material was
enclosed in glass, but not when covered with the thinnest tin plate.
He was astonished to find that the reddening process proceeds more
quickly and more intensively in sunlight if the experimental material
is covered with opaque blue paper, and in greater degree than under
proportionately more transparent yellow and red paper. This is the
earliest (though indefinite) record of the different chemical reactions
of radiation of colors.

In the nineteenth century H. de Lacaze-Duthiers, of Paris, during
a sojourn in Mahon, the capital of the Balearic Island, Minorca, studied
various species of purple snails (Purpura baemastoma and Murex
trunculus) which are found there in the sea. He made exceedingly
interesting experiments with the secretion of these snails and their
sensitiveness to light. These results have been preserved for us. He
published his work in a treatise “Memoire sur la pourpre,” in the
Annal. des sciences naturelles, Zoologie (Paris, 1859). Lacaze-Duthiers
coated linen and silk with the yellow secretion of the purple snails and
exposed them for two days to strong sunlight, thus forming purple dye.
He used the secretion of the purple snail to make drawings of snail shells
and reproduced their images by exposing them to the sun. A drawing
of this kind, made with the juice of Purpura baemastoma in 1858, was
published by Alexander Dedekind in his Ein Beitrag zur Purpurkunde
(Berlin, 1898). Collotypes in color were inserted, which the author
(Eder) had reproduced at the Graphische Lehr- und Versuchsanstalt,
in Vienna, from the original linen images. Other images made with the
secretion of Murex trunculus show a blue-violet shade. As late as the
time of Lacaze the fishermen of the Balearic Isles used the juice of
these snails ( Purpura baemastoma) to mark their laundry, and this
marks the end of early purple dyeing. Nor is it likely that the industry
will be revived, since modern color chemistry can undoubtedly pro-
duce much more brilliant purple dyes.

Later Augustin Lettelier studied the mussel Purpurea capillus, which
is found abundantly along the British coast. He observed that the purple
dye yielded by this bivalve consisted of a yellow substance which
was not sensitive to light, and of two other substances which were
sensitive to light and turned carmine red or violet under the action of
light (“Comptes rendus,” Eder’s Jahrbuch, 1890, p. 279).

i 4 INFLUENCE OF LIGHT ON PURPLE DYEING

The chemical properties of the purple dye were first investigated in
1905 by the highly gifted chemist P. Friedlander, who was called at
that time by W. Exner to the Department of Chemistry of the Tech-
nological Museum for Industry at Vienna. His pioneer investigations
of sulphur derivatives of indigo (thioindigo, etc.) pointed in entirely
new directions in the chemistry of indigo ( 1 905 ) . In the research which
resulted in his discovery of indigo red he arrived at the assumption that
purple dye might be an indigo derivative, like the red indigo. Through
the courtesy of the Imperial Zoological Experiment Station in Triest he
obtained about 1 1,000 snails (Mur ex brandaris). He isolated the purple
dye by coating filter paper with the secretion of the glands and de-
veloped the dye by a short exposure to sunlight. Friedlander found
that the purple was free from sulphur, chlorine, and iodine, but con-
tained nitrogen and, what particularly surprised him, was also rich in
bromine.

Analysis showed that the purple dye was to be considered as a dibro-
mo derivative of indigo or an isomer indirubine. Theoretically, there
can be no less than fifty isomeric dibromindigotines and dibromindiru-
bines. According to Friedlander the purple of the ancients is indentical
with the artificially manufactured 6: 6 dibromindigo, which possesses,
of all isomers which have hitherto been investigated, by far the deepest
shade of red. However, it was still necessary to prove by spectroanaly-
sis that the artificial purple was identical with nature’s product. This
led Professor Friedlander, in 1909, to request his colleague Dr. Eder to
make a spectroscopic comparison of the brominated indigo derivatives
(6:6 dibromindigo) in question with the orginal purple of Mur ex
brandaris. Dr. Eder found that equally strong solutions of both dyes
were identical, both in the qualitative absorption spectrum as well
as in the quantitative spectral analysis. These experiments by Eder are
published as a supplement to Friedlander’s essays in the reports of the
proceedings of the Akademie der Naturwissenschaften. 10 Thus, it was
Friedlander who raised the veil which for centuries had hidden the
true nature of the purple of antiquity. 11

Chapter III. thought and teaching of

THE ALCHEMISTS

Among the alchemists there prevailed confused ideas about the in-
fluence of sunlight. Their views were formed probably less from actual
observation of nature, than through astrological speculations. At any
rate, it is these ideas from which sprang the science of photochemistry,
and this is our reason for occupying ourselves with this interesting
subject.

The alchemist endeavored to find not only a substance which could
transmute baser metals into gold but also an elixir that would heal sick-
ness and prolong life. It was because of this that the term “philosopher’s
stone” was used. Many alchemists believed that the stars and their
conjuctions influenced the success of “the great work.”

Julius Firmicus Maternus (fourth century), who is supposed to be
the first to use the word “alchemy,” deemed it important that an al-
chemist be born under the influence of a good star (for example,
Saturn) that would endow him with the talent: “If he proceeds from
the house of Mercury, he brings the gift of astronomy; from the house
of V enus, he brings song and laughter; from the house of Mars, the love
of arms and instruments; from the house of Jupiter, comes the talent
for theology and jurisprudence; and from the house of Saturn, the
science of alchemy is achieved.” 1

Kallid Rachaidibis, in his work on alchemy “The Book of the Three
Words,” relates in the sixth chapter “On the Observation of the
Planets in the Work of Alchemy,” 2 states that only when the sun is
in certain positions in the heavens, 3 which are there more clearly
explained, “the work of alchemy is achieved.” It follows therefore
that the author did not take into consideration in any way the direct
cooperation of sunlight.

G. Clauder considered as very important the extremely punctilious
observance of the proper season when preparing the philosopher’s
stone. In his “Treatise on the Philosopher’s Stone,” 4 published in 1677,
he mentions that the “World Spirit” was most propitious during the
equinoctial periods; particularly favorable was the spring equinox,
in April and May, also the summertime, when the sun is in Leo. How-
ever, the constellation of the stars must be considered.

Petrus de Zalento 5 also states: “Much of the success of your work
will depend on its beginning being made under the proper auspices of
the stars.”

TEACHING OF THE ALCHEMISTS

Perhaps one might search among the dark secrets of Hermes Tris-
megistos for the root from which sprang the belief of many alchemists
that the stars influence chemical processes. This document, composed
about 4,000 years ago by the “decimal magnitudes,” which according
to the myth was engraved on an emerald tablet, was highly esteemed
by the mystics of all times, and many have attempted to solve its mean-
ing.

The interpretation of the quotation in question is vague. At any rate
it is written:

The father of all things is the sun, the moon is the mother, the wind has
carried in its belly, and the earth has matured it ... . Mount with all the
ingenuity of your senses from the earth to the heavens, then return to
earth and force together into one the upper and lower powers; thus the
honor of the whole world can be achieved, and man will no longer be
despised [after Wiegleb].

In many of the old collections there is still found the conclusion of
Hermes: “The foregoing is entirely the work of the sun.” 8

The writings imputed to Hermes are very obscure, and their inter-
pretation difficult. He attributes all chemic power to the sun, “the
father of all things.” The alchemists interpreted the words “sun” and
“moon” as gold and silver and meant “ the making of gold” when they
spoke of the “work of the sun.” 7 There were many other comments
on the subject. 8 This quotation of astrological superstitution, as well
as a similar one equally ancient, is perhaps from Ostanes, whose manu-
script in Coptic characters was found within a column in the ruins of
the Temple of Memphis. The English translation of the Latin text
(via the German translation by Kopp) 9 runs as follows: “Heavens
above, heavens beneath; stars above, stars beneath; seize these, and you
will be lucky.”

In a similar manner the later alchemists often prescribe the coopera-
tion of the sun; for instance, the exposure of mixtures, compounds,
and such like to the rays of the sun. However, since almost invariably
there are added to the direction 10 for this purpose the words “or in a
warm place,” among others the burying in a warm dunghill— where
light, of course, is entirely shut out— one must conclude that they were
to use the strength of the sun’s rays merely for their mild, heating
energy.

This so-called sun distillation was very common in the sixteenth and
seventeenth centuries, especially in the warm southern countries. The

TEACHING OF THE ALCHEMISTS

distillation apparatus, consisting of distilling flask, condenser, and
receiver, was placed in the sun in the heated sand. They sought to
increase the effect of sunlight by properly placed mirrors, which
caused the rays of the sun to be reflected upon the distilling bulb. A
preparation made in this manner was called “aqua rubi,” which was
used as an eye wash and was very common in Italy at that time.

The alchemist Geber (eighth century) mentions the influence of the
stars in alchemic processes in the first part of his “Chemical Writings”:

Likewise all being and all perfection comes from those stars, as the initial
and perfecting matter of all that is bom and dies, to one entity and not to a
multiplicity .... For everything obtains at once for the time of its ex-
istence from a definite constellation of the stars, that which serves them
best . . . n

A little less mystic and confused is this quotation from Chapter XXIII
“On Gold”:

And therefore we perceive in the work of nature, that copper can also be
changed into gold through skill, for we have seen in copper ore, over
which water flowed, that it carried with it the thinnest and most minute
copper flakes and that it washed and cleansed them by a current constantly
running over the ore; when after a while the water stopped running,
we observed that these same flakes having been cooked in the dry sand for
three years, there was then found under them traces of genuine gold.
Therefore, we believed that the water cleansed and refined it, but that the
warmth of the sun and the dryness of the sand digested and worked the
change of substance . 12

It appears from this passage that Geber attributes to the rays of the
sun, “the warmth of the sun”— the power to transmute base metals into
precious metals as, for instance, copper into gold, if not directly, at least
in combination with other agents. Geber also refined “cerussa” (white
lead pigment) by “congealing in sunlight or moderate fire .” 13 There are
still other scattered astrological references to the influence of the stars
on the success of alchemic labors, but I find no mention of the effect
of light.

The Silesian physician Hans Heinrich Helcher, in his Aurum po-
tabile or “Tincture of Gold,” writes that this preparation together
with the excellence of gold and its analogy with our body is certainly
a curative in effect and use as well as a preservative. In Chapter II,
“On the Excellence of Gold and Its Use in Medicine ...” he says,

1 8 TEACHING OF THE ALCHEMISTS

For none of the metals is purer, more stable, heavier or more perfect than
gold . . . which may be dissolved in spirits and contains the life principle
in itself, like a fire which was imparted to it by the heavens. For this reason,
perhaps, philosophy looks upon the sun as flowing gold or even as con-
taining the great tincture 14 and on that account uses the sign of sun-heavens
as symbol of gold in its books, to indicate that even as the sun in the heavens
exercises its influence on the great world, more particularly in the growing,
noble metal, 16 so gold acts, in the most powerful manner, as a concentrated
light and as the sun’s son, in the small world of man; when well dissolved,
precipitated and active, it shows great efficacy, like the sun. It is unneces-
sary to prove this by citations, because there are so many books at hand,
full of marvelous cures.

Moreover, there is a like quotation from Brandau’s Universal Medi-
cine (ch. i, p. 3 ) :

In gold there are the most precious principia and mineralia . . . namely,
the magnificent, fertile warmth of the sun, the moisture of the moon . . .
resident . . . gold is a son of the heavenly sun; whatever good the sun
does in the great world with its true, mystical rays, that also can his son
gold perform with his subtle, fiery sulphur in the small world, which is
MAN .... Where there is light, there is warmth; where warmth is, there
is life also; and where there is life, there are all kinds of power, forces,
blessings, and fruitfulness.

It is noteworthy that one is cautioned now and then to set out of
doors the “philosophic salt,” viz.; the gold-containing mixture (the
salt) required for the production of the quintessence. It was to be set
out of doors for drying at night, but in daytime it was to be placed in
an airy room or in a place shielded from the sun. 18 There may be a
connection between this statement and the light-sensitiveness of gold
salts, which may have been known to the alchemists.

However, many alchemists undoubtedly express their opinion that
the effect of light rays upon the elixir are favorable. Henricus de
Rochas 17 states that the “heavenly spirit of the universe,” which ani-
mates the elixir, could be incorporated into the matter, especially
through the “warmth and rays of the sun, moon, other planets, or
through dew . . . etc.” Pater Spies, of Cologne, 18 mentions that the
strength of the elixir and its natural fire are augmented by the rays of
the sun. Sendivogius 19 writes that the primary matter of metals, the
“philosopher’s mercurium,” was “governed by the rays of the sun and
moon” .... He also differentiates (following Hermes) between the
“heat” of the sun and that “heat” which is hidden in the center of the

TEACHING OF THE ALCHEMISTS

earth; heavenly and earthly heat, salt, and water must be combined,
and then “all things on earth are created.”

In conclusion, I wish to mention a mystic utterance of an alchemist
who lived at the end of the eighteenth century. I found this hand-
written note of an adept in the HandscbriftenfiirFreunde der geheimen
Wissenschaften, von M. J. F. v. L** (1794) in the library of the well-
known spiritualist and author, Lazar Freiherr von Hellenbach, who
also interested himself a great deal in alchemy and who owned several
manuscripts by alchemists. There we find light praised as the primal
source of things in the following words: “God lives and acts in light;
light acts in spirit; and spirit in salts, salts in the air, air in the water,
and water in the earth.” Thus, the alchemists furnished few positive
data about the nature of the effect of light on matter, or as to the
nature of silver salts in particular, but directed attention to sunlight.

In this respect we obtain the most interesting insight into the
opinions of the alchemists of olden times through the iconographs
and medals preserved to us, which represent symbolically the ideas
and works of the alchemists. It is interesting to note that in these repro-
ductions the image of the sun, which is also that of gold, plays an
important role; but at the same time other symbols are found which
refer to other metals known to the alchemists. For a better understand-
ing of the symbolical representations found on such alchemic gold and
silver medals, I give here an abstract of the more important and most
applied symbols for the materials and agents employed by them: 20

Iron: Mars

<f Y

Salt

Tin: Jupiter

4 \ «

Alum

O cib

Gold: Apollo or Sun

0 d

Salpeter: Saltpeter

Silver: Diana or Moon

C 3

Vitriol

( K

Lead: Saturn

12 r \

9 ? 9

Ash

€

Mercury: Mercury

Sulphur

* *

Copper: Venus

9 9 9

Materia prima

Air

Arsenic

0-0 cud

Earth

Antimony

Water

Caustic potash

Fire

Cinnabar

A crown: in general, the conclusion of the great work

TEACHING OF THE ALCHEMISTS

To Professor Alexander Bauer, of Vienna, we are indebted for the
most exhaustive investigations into alchemic coins and medals. He
describes in several works the rich Austrian possessions of exceeding
rarity and prominence. 21 Two of these medals, in the numismatic
collection of the Ferdinandeum at Innsbruck, are, according to Bauer,
of gold and have come down to us from 1647; among other marks they
contain the sign of the sun. The face and reverse of one of these medals
no doubt has an alchemic origin; it was coined for a particular occasion,
perhaps for a wedding which celebrated at the same time a political
coalition.

The outer inscription reads: Lilia cum niveo copulantur fulva leone
(Lilies of fiery yellow unite with the snow-white lion) ; the inner
inscription: sic leo manuescet sic lilia fulva virescent 1 647 (Thus will
the lion become tamed, the yellow lilies strengthened).

Reverse: in the inner circle, a man striding, in his left hand the
symbol of iron (Mars), in the right a sword (at that time the alchemic
sign for fire) and the inscription: Arma furens capiam rursusque in
praelia surgam (Furious, I shall take up my weapons and rise again
to battle). The inner circle is surrounded by six other small circles
and by the planetary signs of the metals: gold, silver, mercury, copper,
lead, and tin. The legends to these symbols read as follows: for gold
(sign of the sun) : A marte obscuror (I am obscured by iron) ; for
silver: Martis horrore deficio (I am wasted by the horror of war) ; for
mercury: Pedibus Mars abscidit alas (Iron has cut away the wings of
Mercury’s feet) ; for copper: Marti conjungor (By iron I am united) ;
for tin: A marte defendor (lam defended by iron); for lead: A marte
ligor (lam bound by iron) .

The other medal shows an alchemic taler of the alchemist Baron v.
Kronemann, who maintained that he was able to make gold and silver
out of mercury. He made silver coins for special occasions (c.1679),
which are preserved in the Imperial Numismatic Cabinet at Vienna.
Kronemann, who was exposed as a swindler and hanged, 22 engraved
on one of these original coins the picture of a radiant sun, added the
word “tandem” (finally) and in the direction of the rays the words
“per me” (through me) . Perhaps he meant to indicate the necessity of
sunlight for the great work, perhaps the sign of the sun is merely to
indicate the symbol of gold. The reverse of the medal carries again the
sun and the symbols of the three basic principles.

Another noteworthy alchemic medal of gold, weighing 1 6 Vz ducats,

TEACHING OF THE ALCHEMISTS

2 I

is kept in the former Imperial Numismatic Cabinet at Vienna and
comes down to us from 1716. The inscription on this medal relates
that in this year the transmutation of lead into gold was successfully
accomplished in the presence of a number of trustworthy witnesses.
Here, also, the medal carries a symbolic figure of the sun with the
inscription: “A golden progeny sprung from a leaden father.” An
illustration may be found in Bauer’s work Die Adelsdokumente
osterreichischer Alchimisten und Abbildungen einiger Medaillen alchi-
mistischen Ursprungs (1893).

The reverse of this medal carries a Latin inscription which reads
in English:

The chemical change of Saturn to sun, i.e., of lead into gold, was observed
at Innsbruck December 31, 1716, in the presence of His Highness, the
Rheno-Bavarian Count Palatine Carl Philipp, High Steward of His Holi-
ness the Roman Emperor, Great Elector of Bavaria, Duke of Jiilich, Cleve
and Bergen, Governor of Tirol, etc. etc., and this medal was coined to
the everlasting memory of the castle Ambras and posterity £Schmieder,
Gescbicbte der Alcbimie ].

Later works are: Collection d'ouvrages relates aux sciences herme-
tiques AlbertPoisson theories&symboles des alchimistesle grande-ceuvre
suivi d'un essai sur la bibliographie alchimique du XIXe siecle; ouvrage
orne de 1 5 planches, representant 42 figures, Bibliotheque Chacornac,
(Paris, u, Quai Saint-Michel, 1891), and Cosmology; or, Universal
Science, Cabala, Alchemy, Containing the Mysteries of the Universe
Regarding God Nature Man, the Macrocosm and Microcosm, Eternity
and Time, Explained according to The Religion of Christ, by Means
of The Secret Symbols of the Rosicrucians of the Sixteenth and Seven-
teenth Centuries; copied and translated from an Old German manu-
script and provided with a dictionary of occult terms by Franz
Hartmann, M. D. (Boston; Occult Publishing Company, 1 20 Tremont
Street, 1888) .

The alchemists, as we have seen, had only hazy, mystic conceptions
of the influence of the all-animating sun and of astrology on the
successful working out of the chemical processes by which they
endeavored to change base metals into gold and silver. Nevertheless,
their ideas were the starting point for a number of chemical experiments,
which led to the discovery of phosphorescent bodies in the seventeenth
and eighteenth centuries and to the discovery of the light sensitiveness
of the silver salts, as is shown in a later chapter.

TEACHING OF THE ALCHEMISTS

SILVER AND GOLD SALTS

The chemical properties of the salts of silver and gold with their
reactions to light remained unknown for a long time. We shall mention
here only the most important facts from the history of chemistry and
the gradual growth of the chemical knowledge of silver and gold
combinations as far as the history of photography is concerned with
them.

We quote from the author’s Quellenschriften zu den friihesten
Anfdngen der Pbotograpbie bis zum 18. Jabrbundert (Vienna, 1913).

The earliest record of the production of nitrate of silver by dis-
solving silver in aqua fords (nitric acid) and its subsequent crystalliza-
tion is attributed to the half-mythical Geber (Gabir, Dschabir ibn
Hajjam), the most renowned of the Arabian alchemists, who is said to
have lived in the eighth century. He spread the ancient teachings and
ideas about the transmutation of base metals into noble metals. The
latter-day alchemists venerated Geber as their master.

If we disregard these ideas and concentrate upon the practical,
chemical knowledge of the early alchemists, it must first be ftressed
that old Geber was credited with extraordinary chemical knowledge
and with having, among other matters, first mentioned nitric acid.
Modem historical research, however, points to many writings attributed
to Geber as apocryphal; they were probably written by different
Latin writers under assumed names, about the fourteenth to the six-
teenth century and foisted upon Geber’s name. But they report the
experiences of the occidental alchemists of their time.

The passage relating to silver nitrate in the work attributed to Geber;
De inventione veritatis, which was printed in 1 545, 23 reads as follows:
“Next dissolve glowing silver in aqua fortis as before, then boil it for
a day in a long-necked phial with the opening corked, until the water
is reduced to one-third its volume; then put it in a cool place, and
little stones are formed like fusible crystals.” Silver nitrate is thus well
described, but at that time a specific name was not conferred upon the
crystals.

We owe exact and authentic information about silver nitrate to the
celebrated physician Angelo Sala (seventeenth century), born in
Vincenza. He lived most of his life in Germany and in Switzerland,
and in his last days was physician-in-ordinary to the Duke of Mecklen-
burg. He spent a good deal of time in compounding drugs and medi-

TEACHING OF THE ALCHEMISTS

2 3

cines and deserves credit for the development of chemistry and its
application. He introduced the name “magisterium argenti,” or “cry-
stalli Dianae,” and described in his book Opera medic a chimicae (ist
ed., 1647; 2d ed., 1682) the manufacture of the so-called Hollenstein
(caustic stone) by smelting silver nitrate. As Felix Fritz discovered,
a pamphlet by Sala was published under the title Septem planetarum
terrestrium spagirica recensio (1614) in which he reported that
powdered silver nitrate turns a deep black in sunlight. He called silver
nitrate at that time “lapis lunearis” and wrote: “Si lapidem lunearem
pulveratum ad solem exponas instar atramenti niggerimus” (When
you expose powdered silver nitrate to sunlight, it turns black as ink).
He also established the effect on paper, because he saw that silver
nitrate wrapped in paper for a year colored it black.

The well-known alchemist Johann Rudolf Glauber (1604-68), the
discoverer of “Glauber salt,” named after him, mentions in his Expli-
catio miraculi mundi (1653; later ed., 1658):

If an aqua fords is distilled from saltpeter and vitriol and a little silver is
dissolved in it, if then is added common rain water to break up the aqua
fords, there is produced a fluid which dyes coal black, like ebony, not
only all the hard woods, but also furs and feathers ^Glauber, Opera chymica,
1658, p. 190J.

The first intimation of the property of silver nitrate to turn black
when in contact with organic substances is attributed by the old
writers to Count Albert von Bollstadt (Bollstadt is near the small
Bavarian town Lauingen), who was called Albertus Magnus (1193-
1280). He was one of the most learned men of the Middle Ages and
was looked upon as one of the oldest and most renowned alchemists. 24
He was bom in Suebia, entered the Dominican order, taught in several
monasteries in Cologne, Hildesheim, Regensburg, was professor of
theology at the University of Paris, and finally returned to Cologne,
where he devoted the last years of his life entirely to science. Albertus
Magnus died in 1280, at Cologne, where he is buried in the church of
St. Andrew. Owing to his many-sided education and culture, he was
honored with the surname Albert the Great, also as “Doctor univer-
salis.” His works on chemistry and mineralogy were valued very highly
during the Middle Ages, and his views on chemistry, clad in the garb of
Aristotelian philosophy, although naturally highly uncertain, disclose
a profound penetration. Of the metals, he knew only mercury, lead, tin,

TEACHING OF THE ALCHEMISTS

silver, copper, and gold, and he pronounced the alchemic gold which
was brought to his attention a fraud. In his writings he mentions silver
nitrate, and he was familiar with the separation of silver from gold
by means of aqua fortis. In the pamphlet attributed to him, Compositum
de compositis, the celebrated “Doctor universalis” reports the following
about a solution of silver in nitric acid: “It discolors the human skin
with black color which is difficult to remove” (Kopp, Geschichte der
Chemie, IV, 203).

The authorship of this pamphlet has been denied to old Albertus,
according to later investigations of H. Kopp ( Beitrdge zur Geschichte
der Chemie, 1875, III, 77), and is said to have come down to us from
an early unknown alchemist.

THE DISCOVERY THAT CHLORIDE OF SILVER (HORNSILVER) EXISTS
AS A MINERAL IN NATURE, BY FABRICIUS, I 565

Chloride of silver, the “luna cornea” of the alchemists, occurs in
the mineral kingdom as “hornsilver” and is found in the upper levels
of the silver lodes in Freiberg (Saxony) and in other silver mines.
It was recognized as rich in silver ore in the sixteenth century and
was first described by Georg Fabricius in 1565. This happened at the
same time as the reawakening of the descriptive natural sciences in
the sixteenth century, in which period Konrad Gesner especially
stands out as a student of natural sciences and an extensive writer on
the subjects of zoology, botany, mineralogy, and various other depart-
ments of science. This versatile historian, who after many travels
settled down in Zurich as professor of philosophy and as physician, was
also called the “German Pliny” on account of his versatility. Although
most of his efforts were devoted to botany and zoology, he published
also a collective work on fossils, precious stones, minerals, and metals
under the title De omni rerum fossilium genere, gemmis, lapidibus,
metallis . . . (1565). Several scholars of the natural sciences, including
Fabricius, collaborated with Gesner in this work. The part “Ober
Metalle Verwendung undihre Namen” was edited by Georg Fabricius.
Fabricius (1516-71) was bom in Chemnitz, became rector of the
Fiirstenschule at Meissen, after he had previously lived a long time in
Italy as private tutor; he died in Meissen in 1571.

Fabricius was greatly influenced in his studies by the earlier works
of the well-known mineralogist and chemist Georg Agricola (1490-
1555). He acknowledges Agficola’s influence in the Preface of his

TEACHING OF THE ALCHEMISTS

2 5

work De metallicis rebus (Zurich, 1565), which is of special interest
to us, as follows: “Various and learned observations concerning
metallurgy and metallurgical terms, from the papers of GeorgFabricius;
by which especially are explained certain matters which Georg Agricola
omitted.” This work, which discloses an astounding knowledge of the
different silver-bearing ores, was regarded by his contemporaries as
less important than his other philosophical and poetical writings.

The reputation of Fabricius as a poet was so great that he was ap-
pointed poet laureate by Emperor Maximilian II in 1570 and was raised
to the rank of nobility. His poems have long since faded away and been
forgotten, but his work De metallicis rebus has won from posterity
its well-earned recognition. In it we find mentioned for the first time
a kind of translucent silver ore under the name “Argentum Comei
coloris translucidum,” viz., hornsilver, which is nothing else than our
silver chloride. While Fabricius states that hornsilver is of the color
of leather, soft as lead, and that it melts so easily that the flame of a
candle will melt it— he knows nothing of any change by exposure to
light. This point must be stressed, because the French physicist Arago,
in his report on the daguerreotype presented in 1839, adds the follow-
ing: “This substance changed under the influence of light from a
yellowish gray to violet.” The words caused many who copied them
thoughtlessly to believe that Fabricius himself knew and expressed
his opinion on this reaction, which was and is not true. This misunder-
standing led many to repeat Arago’s remarks (with or without mention-
ing the source), thus attributing to Fabricius, until modern times, a
discovery with which he had nothing whatever to do. As early as 1881
I corrected this erroneous opinion that Fabricius knew of the sensitive-
ness of silver chloride to light, which correction has been repeated
for many years in the literature of the subject ( 1 st ed. of my G eschichte
der Photo graphie, 1881; 3d ed., 1905). Nevertheless, this erroneous
view persists and is contained in the work of Colson, Memoires origi-
naux des createurs de la photo graphie (p. 7), as well as in Ludwig
Darmstadter’s Handbuch zur Geschichte der Naturwissenschaften
und Technik (2d ed., 1908, p. 1559).

This protracted uncertainty about the origin of photography is evi-
dently to be traced to the fact that the works of Fabricius have become
very rare and therefore difficult of access. For this reason I added
the Latin context of Fabricius about silver to the German translation
in my Quellenschriften zu den friihesten Anfangen der Photographie

26 TEACHING OF THE ALCHEMISTS

(1913). The title and tail pieces of that work are exact photoengraved
reproductions of the woodcuts from the orginals printed in 1565 and
preserved in the Court Library at Vienna.

The portrait of Georg Fabricius can be found in the Saxonia collec-
tion of the Royal Cabinet of copperplate engravings in Dresden. The
print is probably an engraving dating from the second half of the
seventeenth century, therefore a copy of an older print or of a painting.
Professor Robert Luther was kind enough to have a negative made
from this print in his laboratory for scientific photography in Dresden,
from which the reproduction in rotogravure was made for my fourth
edition. Another picture of Fabricius, a lithograph, is given in his
biography by C. G. Baumgarten Crusius, De Georgii Fabricii vita et
scriptis (1839).

Ever since the discovery of the daguerreotype the writing of the
history of photography has been dominated by the erroneous opinion,
caused by Arago; evidently none of the “history writers” was
acquainted with the very rare Latin booklet of Fabricius. Georges
Potonniee refers to this matter in his Histoire de la decouverte de la
pbotographie ( 1 92 5, p. 60) in a manner which distorts the true circum-
stances. Potonniee denies the originality of Dr. Eder’s explanations.
He relates that the French physicist Ed. Becquerel did not share
Arago’s view and indicated this in his book on physics, La Lumiere
(1868). Becquerel, however, substantiated his assertion by references
to the early original sources; it is therefore hardly surprising that all
later writers on the history of photography (even the French) trusted
rather the authority of Arago than the vague utterances of Becquerel,
to whom nobody paid any attention. The author opposed this con-
fusion of facts first in 1881, and his view was accepted thereafter by
the literature of the profession. Mr. Potonniee commits an error when
he writes: “The same information is given by Fabre” in his Traite
ency elope dique de pbotographie (1889-90).

It is evident that Potonniee had before him only the second and
third editions of Eder’s Geschicbte, dated 1892 or 1905, and did not
take the trouble to refer to Eder’s decisive first publication of 1881
in order to confirm the historical chronology. Had he done this, he
could not have overlooked the fact that C. Fabre wrote eight years later
than Eder. Eder corresponded with this distinguished author in the
department of scientific photography, and it is gratifying to note that
Fabre supported Dr. Eder in his conclusions. Of course Fabre never

TEACHING OF THE ALCHEMISTS

claimed any priority. Waterhouse also supported Eder’s statement
{Phot. Journal, June, 1903).

THE PRODUCTION OF CHLORIDE OF SILVER BY THE WET PROCESS BY
ALCHEMISTS IN THE SIXTEENTH AND SEVENTEENTH CENTURIES

BASILIUS VALENTINUS

The wet process of producing silver chloride from a solution of
silver nitrate with sodium chloride, which afterward became so impor-
tant in photography, was certainly known very early. This discovery
was credited for a long time to the mysterious old alchemist and analyst
Basilius Valentinus, who was alleged to be a Benedictine monk and
lived about 1413 in St. Peter’s Monastery in Erfurt. Modern research
has proved this story to be untrue, since such an individual never
existed. The writings published under his name are said to have been
collected and published long after his death. There were many editions,
in which were set down many very important chemical discoveries
by different anonymous alchemists. 25

In the writings of this so-called Basilius Valentinus, then, are gathered
the observations of several authors. 28 Many parts dealing with chemis-
try and alchemy were purloined from Paracelsus, some of them from
analytical chemistry. The whole style of the so-called “Basilius
Valentinus-Schriften” is Paracelsic, showing the effort to imitate
Paracelsus, while copying him all the time. These writings date from
the second half of the sixteenth century and carry the names of several
authors and compilers. Modem research has ascertained that Nikolaus
Soleas, a Bohemian, was the author of at least part of the “Letzte
Testament.” It is certain that Johann Tholde, the publisher of this
so-called “Basilius Valentinus-Schriften,” is not the author. Tholde’s
works are entirely different in presentation and style of thought. The
first pamphlet which was published under the name “Basilius Valen-
tinus” bears the title: Ein kurtz summarischer Tractat Fratris Basilii
Valentini des Bene dieter Or dens, von dem grossen Stein der Uralten
(Eisleben, published by Johann Tholde 1 599) .

Tholde is the publisher of the following works: two reprints of the
above book (Leipzig and Frankfurt, 1601); Von den naturlich und
obernatiirlichen Dingen and De occulta Pbilosopbia; oder, Von der
beimlichen W under geburt der 7 Planeten (Leipzig, 1603); Halio-
graphia (Leipzig, 1 603); Triumph -W agen Antimonii Basilii Valentini
(Leipzig, 1604), which is one of the most famous works. In the latter

28 TEACHING OF THE ALCHEMISTS

work there is found a remark, erroneously credited to Roger Bacon,
which speaks of the fusibility of artificial silver chloride.

Later, George Claromontanus, in Jena, published Das letzte Testa-
ment des Basilius Valentinus (1626?; 2d ed., 1651, by C. Dietzel, Strass-
burg) . This is the most important and earliest printed matter.

The main sources, as we have shown, of the “Basilius Valentinus-
Schriften” are taken from Paracelsus, and some parts are taken from
the metallurgical-alchemistic works of Nikolaus Soleas; indeed, the
latter is absolutely the author of several parts of the “Basilius Valen-
tinus-Schriften.” The other authors remain unknown.

The title of the pamphlet about mines (Zerbst, 1600) by Nikolaus
Soleas reads as follows: Ein Biichlein von dem Berg'wergk avie man
dasselbig nach der Rutten und Witterung bavuen soli sebr dienstlich
und zuavissennotigdurch Nicolaus Soleam Boemum zu Kauff getragen
Jtzt durch Eliam Montamum, Fiirstlichen Antaltisten Leib-Medicum
zum Briege. Erstlich an Tag geben.

Recently Felix Fritz (Berlin) made researches into this so-called
“Basilius Valentinus” and published his valuable investigation in the
Zeitscbriftfiir angewandte Chemie ( 1925 XXXVIII, 325), which was
edited by Gunther Bugge, Franz Strunz, Ernst Darmstadter, Lipp-
mann, and other historians of natural sciences.

The Chymischen Schriften des Basilius Valentinus were not printed
until 1677, which was several centuries after his death. In Book IV of
Chymischen Schriften, called “Handgriffe,” is a remark that sodium
chloride, or cooking salt, in a silver solution produces a precipitate,
while it is suggested there that “copper as well as common salt pre-
cipitates silver.” Of course, in the first case metallic silver is formed,
while in the latter it is silver chloride.

Although a pseudonymous author wrote under the name Basilius
Valentinus about silver salts, it is plain from the surrounding circum-
stances that the preparation of silver chloride by the wet process was
known to a wide circle of alchemists. This is established by the wide-
spread and celebrated writings of the German physician and alchemist
Oswald Croll (Crollius). He taught, in his essays printed in 1608,
how to deposit silver chloride by a solution of silver nitrate in cooking
salt, how to purify by water, and how to produce hornsilver artificially,
which he called “luna cornea,” according to the alchemistic symbol
for silver, which was expressed by the sign “luna,” the moon. It is
remarkable that Crollius did not claim priority for all his statements,

TEACHING OF THE ALCHEMISTS

since he writes in the memorial Preface to his Basilica chymiccP that
he communicates to the public use:

What I have learned in nearly twenty whole years in my many different
perilous and laborious travels in France, Italy, Germany, Hungary, Bohemia,
and Poland from the most celebrated alchemists and learned men, partly
through great gifts and exchange of my secrets (not mentioning my own
practice and inventions), learned and experienced through untiring dili-
gence and careful investigation . . .

The first edition of the Basilica chymica of Crollius was published
in 1608, a year before his death. It went through eighteen editions; a
German edition appeared in 1657 at Frankfurt a.M. Crollius is repre-
sentative of the school of thought and research of his time in the
sphere of alchemy, theosophy, and medicine; that is why the author
reproduced in his Quellenschriften large parts of the text as well as
the highly interesting front page of this first edition of Crollius. The
title page displays the portraits of those masters of alchemy whom he
esteemed among his predecessors— the mythical Hermes Trismegistos,
Geber, Morienus, Roger Bacon, Raimundus Lullius, and Theophrastus
Paracelsus. The name Basilius Valentinus is not among them, therefore
it is questionable whether Crollius derived the preparation of silver
chloride from earlier sources or discovered it through his own experi-
ments. At any rate, he contributed most, among all the alchemists
of his time, to the spread of the knowledge about the production of
silver chloride by the wet process.

ROBERT Boyle’s RESEARCHES IN 1 667 CONCERNING SILVER CHLORIDE
AND OF ITS PROPERTY OF TURNING BLACK IN THE AIR

From the excerpts given above of the general condition of chemistry
until the beginning of the seventeenth century, it must be evident
that the conception of the chemical processes of nature was permeated
by mystic and cabalistic errors. About the middle of this century,
however, exact natural science gradually forced its way to the front,
and especially Robert Boyle (born at Lismore, Ireland, 1627, died in
London, 1691, where he lived for a few years) insisted on exact
knowledge based on experiments in chemical and physical phenomena.
Boyle was one of the founders of the celebrated English scientific body
The Royal Society and one of the directors of the powerful East India
Company. He combated many of the alchemic superstitions of his

TEACHING OF THE ALCHEMISTS

3 °

time, as well as the old theory of the four basic elements, and he
defined the term “element” as a substance which cannot be further
decomposed. He also studied the laws governing gases and was one
of the first to give a good deal of time to experiments leading to the
knowledge of chemical affinities.

Among his most important writings are Experiments and Consider-
ations upon Colours (1663), published in Latin at Geneva, 1667,
with the title Experimenta et consider ationes de coloribus. They are
also contained in the English collection of Boyle’s works (London,
1772), which is adorned with Boyle’s portrait.

Boyle represented the viewpoints that light was of a material nature
and that heat could be weighed. He also described, among other things,
many chemical reactions and resulting changes of color. He communi-
cated his experiments to a friend, whom he called Pyrophilus, in the
form of letters. Pyrophilus is a name by which he addressed himself
in the third person. He described also the effect of acids and bases on
vegetable dyes (for instance, the change of color in litmus, the juice
of buckthorn berries, Rbamnes cathartic a, violets, etc.). In a lengthy
series of experiments he mentions chemical changes of color of all
kinds, and he arrives through this investigation at the mention of
chloride of silver. In “Experimentum XXXVI” of this book we find
a very important passage relating to the history of photography, where
he describes the deposit of the white chloride of silver and the phe-
nomenon that it turned dark under exposure “in the air.” It is true
that he did not realize the cause of the darkening, which is an effect
of light, but attributed it to the action of air. At any rate, it was
through his experiments that the knowledge of silver chloride was
greatly enlarged, which prompted the author to include in his work
Vber die friihesten Anfdnge der Pbotograpbie the text of the “Experi-
mentum XXXVI” from Boyle’s Latin edition Experimenta et con-
siderations de coloribus, together with a German translation. The
sober and pointed observations of Boyle differ strikingly from the
confused mystic and extravagant statements, not only of his prede-
cessors but also of many of his successors (for instance, Balduin).
However, the road, beginning with the discovery of silver chloride
and leading to an explanation of the true causes of its darkening by
light, was still a very long one.

At that time Boyle’s conception of that theory was not carried any
further. For instance, Lemery in 1675 writes in his Corns de chymie

TEACHING OF THE ALCHEMISTS

(9th ed., Paris, 1698, p. 1) about chloride of silver: “the precipitate
deposits simultaneously with the salt or with the copper, drying, and
even in the shadow it turns brown which is no doubt because of
the small amount of copper which it contains.” This proves that Lemery
noticed that silver chloride would darken even in the shade. Instead
of pursuing these investigations further, however, he presumes that
the discoloration was caused by the presence of a trace of copper
(Felix Fritz, Phot. Industrie, 1925, p. 586).

It is interesting to note that the old scholars, even those who special-
ized in the theory of light, gave us such extremely meager suggestions
of its chemical effects. This applies not only to the ancient Greeks
but also to the Arabs. 28

Celebrated scholars of a later era, like Roger Bacon ( 1 2 1 4-94) , Porta
(1538-1615), Kepler (1571-1630), Huyghens (1625-95), Newton
( 1 642 -1727), who prepared the way for new advances in the science
of optics, overlooked the influence of light on the intricate nature of
matter.

In the sixteenth and seventeenth centuries there emerged the inven-
tion of the camera obscura and of nature prints, both of which are
of such importance to the history of the invention of photography
that we shall enter upon this discussion subsequently more closely.

homberg’s experiments with staining and blackening
OF bone by exposure to sunlight, 1694

In 1694 the German advocate Wilhelm Homberg (b. 1652, in
Batavia) offered noteworthy communications about silver nitrate.
He was induced to study chemistry in 1674 by Otto von Guericke of
Magdeburg and traveled in Italy, France, England, Holland, Sweden,
and Hungary in order to pursue his studies in the department of the
natural sciences and medicine. He visited Paris several times, where he
was elected a member of the Academy (1691) and where he died in
I7I 5 .

On September 4, 1694, Homberg delivered, at a meeting of the
Academie Royale des Sciences, in Paris, several communications on
his various experiments. 20 In the Histoire de /’ Academie Royale des
sciences a Paris, depuis 1686 jusqu'a son renouvellement en 1699 (II,
129, point 7) he gives a note on the etching of bone by a solution of
nitrate of silver and having blackened it in sunlight. The quotation
reads: “Homberg has shown a small marbled box made of beef bone

TEACHING OF THE ALCHEMISTS

which had been soaked in dilute aqua fortis in which silver had been
dissolved. This bone was then exposed to the sun to be blackened; then
it was put in a lathe to give it a marbled appearance.”

From this account it appears that Homberg showed at the Academy-
in Paris, in 1 694, a small marbled box made of beef bone. He had dipped
the bone in a solution of nitrate of silver and had blackened it by
exposing it to sunlight. He then mounted the bone in a lathe and,
by the process of turning it, laid bare portions of the whitish bone
below the blackened surface, thus giving the box a grained or marbled
appearance.

Thus, the result of Homberg’s experimenting was no more than the
marbling of bone previously dipped in silver solution and blackened
by exposure to light. It never occurred to him to differentiate between
the action of light and heat in the process of blackening, and he made
no attempt to place a stencil or string over the silver-impregnated bone
to produce a photographic silhouette, as Schulze did later. Schulze
knew well the difference between the effect of light and of heat and
used light for the production of his stencil images. This made him the
first to discover the chemical action of light on silver salts and their use
in the photographic process.

Whereas in the seventeenth century sunlight and heat, celestial light
and atmospheric air, were not kept apart as agents, it seems the some-
what belated dragging in of an idea, which Homberg did not express
anywhere in his publications, when an author (Fritz) insists that “he
[Homberg] discovered the change of silver nitrate by light in the
presence of organic substances.” It is difficult for us to appreciate what
reads today as seemingly naive reports of the individual experiments
of the old natural philosophers, although they appeared generally
quite proper and interesting to them. If, for instance, one reads what
Homberg writes in another place, that a cat died under the bell glass
of an evacuating air pump, on the exact fourth stroke of the piston,
and so forth, one would expect that Homberg would have stated
at least that the silver-impregnated bone would turn black on the sur-
face, exposed to sunlight, and not on the under side; which is what
Homberg would have been compelled to state, if he had been conscious
of the effect of light and shade.

Homberg did not realize the correct nature of the phenomena which
entered into the staining and blackening of the bone. He believed,
no doubt, that he faced the effect of sun heat and that is why he failed

EXPERIMENTS WITH NATURE PRINTING

to connect the demonstration of his little blackened and turned bone
box, impregnated with silver salts, with the discovery of the effect of
light action on silver. Consequently, despite the great interest awakened
by Homberg’s experiment (sensitizing of bone in silver nitrate and
blackening through exposure to sun) his work had no influence worthy
of remark on the advancement of photochemistry in his time, and his
contributions in no way interfere with Schulze’s claim to priority.

Closer and more careful observation would have shown that the
bone impregnated with silver nitrate darkened first on the side exposed
to the sun, while the side not so exposed to light action darkened much
more slowly.

Chapter IV. experiments with nature-
printing IN THE SIXTEENTH AND SEVENTEENTH
CENTURIES

Subsequent to the invention of the printing art in the fifteenth cen-
tury the method of illustrating printed matter with engraved wood
blocks (wood engraving) achieved great importance, as did also the
art of copper-plate engraving. Numerous works of the sixteenth
century are illustrated in this manner. Even at this early period
naturalists and publishers of works on botany were compelled, owing
to the great cost of wood and copper-plate engraving, to investigate
the possibility of using plants, leaves, and so forth, for making impres-
sions directly. The earliest works of this kind, no matter how bad or
primitive, seem to have been accepted as sufficiently satisfactory. This
is borne out by the fact that such prints were frequently and favorably
mentioned and that the process was recommended for imitation.

Leonardo da Vinci was, it appears, the first to experiment in the
fifteenth century with the making of copies from plants. 1 He writes
in his great atlas-shaped manuscript “Codex Atlanticus,” which he
probably began in 1490 and which he continued until the end of
his life (1519), on page 72, as follows:

The paper must be coated with lampblack, mixed with sweet oil, and
then the leaf of the plant must be colored with white lead, dissolved in
oil, as is done with type on the printing press. It is then printed as usual.

EXPERIMENTS WITH NATURE PRINTING

and so the leaf (i.e., the impression from it) will appear dark in the low
parts and light in those pans which are high . . .

Leonardo attached an impression of such a nature print from a Salvia
leaf ( Salvia officinalis) to his manuscript.

The subsequent history of nature printing was investigated in detail
by Karl Kampmann at the request of the author at the Graphische
Lehr- und Versuchsanstalt (Eder, Jahrbuch fur Photographic, 1899,
p. 133). His treatment of the subject is adopted in the following pages.
The writings of Leonardo da Vinci did not become known until the
eighteenth and nineteenth centuries, so that the first printed description
of nature printing from plants must be dated earlier. These products
of nature printing were described under the name “Ectypa plantarum”
in the work on art of Alessio Pedemontese (Alexis Pedemontanus, as
others called him), Milan, 1557, which was translated into German
in 1593 by Hans Jacob Wecker, city physician at Colmar. In 1665
M. de Monconys ( Journal des voyages, Lyon, Vol. II) described the
method of printing from plants, which he had learned in Rome from a
Dane by the name of Walgenstein (Welkenstein).

In the Court Library (now National Library) at Vienna, there is a
work by the French professor De la Hyre which contains nature
prints from the seventeenth century. This was shown to his Majesty
the King of Sweden, on his visit to the library, as the earliest work
produced by nature printing ( Neues Wiener Abendbl., February 26,
1904, p. 3), but this was an error, because, as mentioned above, there
are earlier claims for priority extant. 2

In the book Nutzlicher und curieuser Kunstler (Nuremberg, 1728),
we find the recipe, “To print a natural leaf with all its veins,” very
much on the same lines as advised by Pedemontese. Many similar de-
scriptions are to be found in this period. Even the apothecary’s assistant
at the court pharmacy at Mayence, Ernst Wilhelm Martius, published,
in 1785, a small work of his own under the title Neueste Anweisung,
Pflanzen nach dem Leben abzudrucken, Wetzlar; and J. Conr. Giitle
offers in his work XJber die Kupferstecherei (1793, p. 1 19) a descrip-
tion of how plants can be printed, according to the book by Martius.

In 1798, at Brandenburg, was published J. H. A. Dunker’s Pflanzen-
belustigung oder Anvueisung, wie man getrocknete Pflanzen auf eine
leichte und geschwinde Art sauber abdrucken kann with five black-
and-white and five color illustrations; this ran to a second edition.

EXPERIMENTS WITH NATURE PRINTING

As late as 1809 Graumiiller published in Jena his Neue Methode von
natiirlichen Pflanzenabdriicken in- und auslandischer Gewdchse.

The process for the production of these impressions consisted at
first, according to the reports of the authors quoted above, in holding
the dried plant in the smoke of an oil lamp or candle until it had become
completely and evenly blackened with soot. It was then put between
two pieces of soft paper and rubbed with a folder or by hand until
the soot had been transferred to the paper, whereby two impressions
were produced simultaneously. In later years in place of lampblack,
either the ordinary printing inks used in type printing or that used
for copper-plate engravings was employed. Sometimes a color ink (red,
brown, etc., according to taste) was used, which was mixed with sticky
varnish, and less perishable impressions were obtained by this method.
These Ectypa were generally very defective and imperfect, and the
process was a very slow one, because the inking of the plants with
printers’ ink-balls took a great deal of time. The requirements of
larger editions also necessitated that many plants of the same species
had to be prepared, to yield the necessary number of impressions,
since, of course, a single plant would permit of only a very limited
number of copies, no matter how carefully is was handled.

The nature prints produced by this method were in one color, either
black, brown, or red; these prints were then painted in by hand in their
respective full colors. However, the epidermis of most species of leaves
was often so thick that the delicate veins (the skeleton) did not show
in sufficient relief. This led to the reduction of the leaves to their
skeletons by maceration, that is, by stripping away the upper and
lower skin of the leaves either in water or with an acid, thus leaving
only the perfectly clean framework of the leaf. Antonio Mizaldi
( 1 560) was supposed to have been the first to do this skeletonizing,
and Marc Aurel Severin (Nuremberg, 1645) succeeded even in pre-
paring the leaf of an Opuntia (genus cacti) so that “all flesh was
away and nothing remained but the hard fibers.”

Early books illustrated by this method are not rare and may be
found in most of the larger libraries. Especially rich in such works,
however, is the Hofbibliothek in Vienna. A noteworthy example is
a manuscript dating from 1685, the work of a Cistercian monk, Silvio
Boccone. “Disegni naturali et originali consacrati Alla Sua Maesta
Cesarea di Leopoldo Primo usw. Monaco Cisterciense .” 3 (Folio, 42
tables with 82 illustrations of plants. Wiener Hofbibliothek, No.

3 6 THE HISTORY OF THE CAMERA OBSCURA

1 1,102). The title and dedication run: “Eurer Kaiserl. Majestat unter-
tanigster ergebenster Diener im Herrn Don Silvio Boccone, Zister-
ziensermonch.” The oldest examples of these nature prints extant were
reproduced for the first time in the author’s Gescbickte der Photo-
grapbie, in 1905.

Among other noteworthy examples, the works of Professor Kniphof
must be mentioned. It is known that Professor Joh. Hieron. Kniphof
carried on nature printing (1728-1757) in a business way and in-
stalled his own printing establishment, for which purpose he allied
himself with the printer and bookseller C. R. Funke, of Erfurt.
Many works illustrated by this method originated there and are
accessible in the Hofbibliothek at Vienna. Worthy of mention, also,
are the publications of Seligmann 4 (1748) and others. All these impres-
sions are produced by coloring the plant and pressing it against paper.
This procedure did not afford a real graphic printing process, for
it did not supply a firm and sufficiently uniform printing surface.

From these early efforts, however, sprang the germ which devel-
oped, in 1852, into the process of nature printing invented by Hofrat
Auer, director of the Government Printing Office at Vienna. This
process is based on the use of intaglio printing plates produced by
mechanical casts of the natural objects, mostly from subsequent
galvano-plastic molds. This yielded prints of superior quality and
was of importance for the beginning of the photochemical proc-
esses (see Pretsch, Pboto-galvanograpby; see also the material on
Woodburytype) .

Chapter V. the history of the camera

OBSCURA

The camera obscura 1 in the form of a box with a small hole through
which the eye could view the scene is the predecessor of the photo-
graphic camera. Mention of the formation of pictures projected through
a small aperture is found in the words of Aristotle (384-322 b.c.).
More exact accounts of the observation of eclipses with a species of
pinhole camera are mentioned by the old Arabian scholars and their
followers, as may be seen in the comprehensive studies of Eilhard
Wiedemann. Wiedemann (Eder, Jabrbucb fur Fbotographie, 1910,

THE HISTORY OF THE CAMERA OBSCURA 37

p. 12), dates the first mention of such a camera from 1038 and publishes
a dissertation of the Arabian savant Ibn al Haitam (d. 1039) which is
of importance in the history of the camera obscura. The learned Arab
writes in his essay “On the Form of the Eclipse” that he had in this way
observed the sickle-like shape of the sun at the time of an eclipse.
Abridged, the introduction to his exposition reads as follows:

The image of the sun at the time of the eclipse, unless it is total, demon-
strates that when its light passes through a narrow, round hole and is cast on a
plane opposite to the hole it takes on the form of a moonsickle (Hilal) .

The image o f the sun shows this peculiarity only when the hole is very
small. When the hole is enlarged, the picture changes, and the change
increases with the added width. When the aperture is very wide, the
sickle-form image will disappear, and the light will appear round when
the hole is round, square if the hole is square, and if the shape of the open-
ing is irregular, the light on the wall will take on this shape, provided that
the hole is wide and the plane on which it is thrown is parallel to it.

He then presents as illustrating the sun-sickle, a proof, which as
a whole is correct and is supported by numerous diagrams, together
with a discussion of the possibility of varying the size and shape of
the picture by increasing the distance between the aperture and the
projection wall.

Some historians assert that Roger Bacon, an English Franciscan friar
(1214-94), invented the camera obscura. They support this with the
following remark by Bacon concerning the projection of aerial images.
“The images appear at the point of contact of the light rays with the
perpendicular plane, and things appear there, where there was nothing
before.” Bacon was one of the most ingenious philosophers and scien-
tists of his time, and to him is ascribed not only the invention of the
camera obscura but also of the telescope, of spectacles, a self-propelled
wagon, a flying machine, gunpowder, and so forth. He was suspected
of practicing sorcery, and he had to send his pupil Johannes to Rome
in 1266 in order to purge himself of this accusation. Although there
are passages in Roger Bacon’s writings which are looked upon by some
as possibly referring to the camera obscura, it cannot be proven as a
fact that he invented it.

Goethe, who concerned himself with Bacon exhaustively in his
Farbenlehre (1810, Vol. II), expressed the opinion that many state-
ments issuing from the far-seeing and mentally active, brilliant man
were only conclusions, perhaps only daydreams, which were in antici-

38 THE HISTORY OF THE CAMERA OBSCURA

pation of what both he and his time could offer. Goethe remarks:

Those who are familiar with the ability of the human mind to rush ahead,
before technique can overtake it, will find here nothing unheard of. Roger
Bacon claims that through glasses which he describes one can perceive
with his own eyes not only the most distant objects as quite near but also
the smallest, enormously large. He asserts, also, that images can be thrown
into the air, into the atmosphere, so that they may be seen by a crowd
of people. Even that is not without reason. Many natural phenomena
which are based on refraction and reflection— the camera obscura, which
was invented much later, the magic lantern, the solar microscope and
their different applications— have established almost literally his predictions,
because he foresaw these results. But the manner in which he expresses him-
self concerning these matters indicates that his apparatus worked only in his
brain and that therefore many imaginary results may have originated there.

Levi ben Gerson (d. 1344), alias Leon de Bagnois (see the Jewish
Encyclopaedia, VIII, 26) who was versed in Arabic literature, de-
scribed the camera obscura in his work, written in Hebrew and trans-
lated in 1342 by Petrus de Alexandria under the title “De sinibus,
chordis et arcubis.” He employed the camera obscura in a manner
similar to that of his predecessor Ibn al Haitam in his investigations
of the eclipses of sun and moon.

A quotation, perhaps more intelligible, but still not quite clear,
which might be considered to be the description of a camera obscura,
appears in a work of the architect Caesare Caesariano, who published,
in 1521, at Como, a commentary on Vitruvius’s Treatise on Archi-
tecture. He makes a remark, in elucidation of a misunderstood state-
ment by Vitruvius, which would indicate that the Benedictine monk
Dom Papnuzio, or Panuce, was familiar with the camera obscura.
Caesariano writes that Papnuzio had fastened a concave glass screen,
through the center of which he had bored a hole, in a closed window
of a dark room, and so obtained colored images of exterior objects on
a piece of paper. It is established that this happened before 1521. At
any rate, the description is so vague that several historians 2 refuse to
accept it as a true presentation of the camera obscura.

LEONARDO DA VINCI IS THE FIRST TO GIVE AN ACCURATE
DESCRIPTION OF THE CAMERA OBSCURA

The first clear description of the camera obscura, which projected
images of exterior objects of all sorts through a small wall opening

THE HISTORY OF THE CAMERA OBSCURA 39

upon the opposite wall of a darkened room, is found in the manuscripts
of the celebrated genius of the Renaissance, Leonardo da Vinci
(1452-1 5 19), 3 who was a pioneer not only in the arts but also in the
natural sciences, engineering, and anatomy. In his “Codex Atlanticus”
(see MSS L. da Vinci’s Vol. D, fol. 8, in the Bibliotheque Nationale,
at Paris; E. Muntz, see footnote 3) Leonardo writes:

If the facade of a building, or a place, or a landscape is illuminated by the
sun and a small hole is drilled in the wall of a room in a building facing this,
which is not directly lighted by the sun, then all objects illuminated by
the sun will send their images through this aperture and will appear,
upside down, on the wall facing the hole.

In another place Leonardo da Vinci reports his observation of the
significance of the eye as a camera obscura, for he says:

The experience which demonstrates how objects send their reflex images
into the eye and into its lucid moisture is exhibited when the images of
illuminated objects enter through a small round opening into a very dark
room. You will then catch these pictures on a piece of white paper, which
is placed vertically in the room not far from that opening, and you will
see all the above-mentioned objects on this paper in their natural shapes
or colors, but they will appear smaller and upside down, on account of
crossing of the rays at the aperture. If these pictures originate from a
place which is illuminated by the sun, they will appear colored on the paper
exactly as they are. The paper should be very thin, and must be viewed
from the back; the aperture must be bored through a small, very thin
piece of metal.

This clear description by Leonardo da Vinci and the documented
explanation of the principle of the camera obscura stand out so vividly
against the vague descriptions of his predecessors that one must agree
with E. Muntz, who states:

Accordingly there can be no doubt that Leonardo da Vinci not only
knew the principle of the camera obscura but also, with his usual pene-
tration, probably discovered it. His genius is worthy of the honor of
this and many other inventions and discoveries. But it is a question whether
his discovery really was of any use to his own or the succeeding genera-
tion; whether these, like so many other observations of Leonardo, did not
remain hidden in obscurity. His writings, for which, as is well known, he
used mirror writing, and which were therefore very difficult to read,
have appeared in print, in complete form, only within the last few years.
Undoubtedly he demonstrated the marvels of the camera obscura to some

4 o THE HISTORY OF THE CAMERA OBSCURA

of his acquaintances, but we do not know whether these persons dis-
seminated the information; for instance, had B. Papnuzio heard of it, or
was the discovery started anew by others independently of Leonardo’s first
achievement?

In the first half of the sixteenth century we find the camera obscura
employed on several occasions for the observation of astronomical
phenomena. In Germany, Erasmus Reinhold (1540) and his pupils
Gemma Frisius, Moestlin, and others made observations of the eclipse
of the sun with the aid of a pinhole camera. Girolamo Cardano pub-
lished in 1550, on page 107 of his book De subtilitate, a process which
was intended to improve the camera obscura by inserting a glass
screen into the shuttered panel carrying the aperture of a camera ob-
scura (“orbem e vitro,” by which presumably a lens is meant).

JOHANN BAPTISTA PORTA, IN I 553, WAS THE FIRST TO MAKE MORE
GENERALLY KNOWN THE CAMERA OBSCURA (PINHOLE CAMERA)

The Italian Giovanni Baptista della Porta was born in Naples (1538)
and died there (1615). He was the first who described in clear, univer-
sally comprehensible language the pinhole camera (camera obscura)
in his widely read book, which reached numerous editions, Magiae
naturalis; sive, De miraculis rerum naturalium, 1st ed., 1553, and thus
made it known in the widest circles. At that time the manuscripts of
Leonardo da Vinci, which were written in cipher (mirror writing),
were unknown; they were not printed until several centuries later.
It is highly probable that Porta knew nothing of Leonardo da Vinci’s
invention, and he, as well as the historians of subsequent centuries,
therefore believed himself to be the first to have invented the camera
obscura and the first to have described its marvelous properties.
Although it was shown by later investigations that other scholars were
entitled to claim priority in the invention of the pinhole camera, this
does not in any way minimize the fact that Porta merits the distinction
of having issued the first publications respecting the camera obscura.

In addition, Porta actually announced in the first edition of his book
a novelty, namely, the use of a concave mirror for the production of
images in the camera obscura. He states:

Now I want to announce something about which I have kept silent until
now and which I believed that I must keep secret, how one can see every-
thing in its colors as desired: place opposite the aperture a mirror which

THE HISTORY OF THE CAMERA OBSCURA 41

does not disperse the rays, but unites them and move it forward and back
until you recognize that the picture is in its proper size . . .

Porta projected a reversed picture on a paper screen fastened on top
of the aperture. The aperture which acted thus as diaphragm could
be proportionately larger; according to a remark in the second edition
the aperture was the size of the small finger (see F. Paul Liesegang’s
“Ausfiihrungen” in Mitteilungen zur Gescbichte der Medizin und
der N aturwissenschaften, 1919, XVIII, No. 1 ) . At any rate, it is remark-
able that the chapter in which Porta describes the camera obscura is
entitled “On Other Actions of the Concave Mirror.”

Porta is one of the most interesting figures of the sixteenth century.
He paints a true picture of the conditions prevailing at that time with
regard to the knowledge of physics in his Magiae naturalis, the first
edition (1553) of which he wrote in his fifteenth year. He dealt, in no
less than twenty volumes, with the most varied subjects with a strange
mixture of superstition and knowledge.

He had written, among other things, of the witches’ ointment
{laniiarum unguentum) , was denounced by a Frenchman, and incurred
the suspicions of the Roman court, before which he was accused as a
magician and a poison mixer. Porta was summoned to Rome to defend
himself. He protested that he undertook his investigations only for the
purpose of exposing the fraud which had been carried on with the mat-
ter in question. Although he was acquitted of the charge, the Academia
degli Secreti, which he had founded in his own house, was closed by
order of the Pope. He made many journeys through Italy, France, and
Spain, in order to perfect his knowledge of the natural sciences and to
make his published works, which followed each other very fast, ever
more and more perfect.

A portrait of Porta is to be found in his work La fisonomia dell ’
huomo et la celeste; I have before me the edition printed in 1668 in
Venice, in which a comparison is shown of human and animal phys-
iognomy, with numerous illustrations. The constellations of the stars
are also discussed in this work.

After Porta’s description of the camera obscura had made it widely
known, this apparatus was often employed by pseudo-magicians for
shows of all kinds, especially for conjuring up the devil, and all kinds
of variations were devised, which would offer still more wonderful
performances. It is worthy of notice that considerably enlarged copies

THE HISTORY OF THE CAMERA OBSCURA

4 *

of pictures were made even then with the camera obscura. In later
years the magic lantern replaced the camera obscura for this purpose
A detailed and exhaustive description with indication of the sources
is found in F. Paul Liesegang, “Schaustellungen mittels der camera
obscura in friiheren Zeiten” {Opitische Rundschau, 1919, Nos. 31-33).

THE USE OF A CONDENSING LENS IN THE CAMERA OBSCURA BY
BARBARO (1568) AND PORTA ( I 588)

The Venetian nobleman Daniel Barbara must be credited with the
first description of the use of a biconvex lens in the camera obscura,
for he describes on page 192 of his work La pr attic a della perspettiva
(1568) the combination of the lens and the camera obscura. 4 He used
the spectacles of a man who had grown far-sighted and described
clearly the effect of the lens and its application in perspective drawing.
He also discussed the effect of the use of the diaphragm to improve
the definition of the image. This publication was issued twenty years
before the second edition of Porta’s Magiae naturalis, in which he
seems to describe the use of the camera obscura with a convex lens
as if it were his own invention. A portrait of Daniel Barbaro, found by
Major General J. Waterhouse, in London, is a reproduction from a
copper plate engraved by Hollar from the painting by Titian (Phot.
Jour., 1903, No. 8). Another portrait of Barbaro, by Paolo Veronese,
is in the Dresden Gallery, where also a copper plate engraving by
Houbraken can be found.

Giovanni Battista Benedetti, a Venetian patrician (1585), also knew
of the use of the lens in a camera obscura. It was much later that Porta
described the camera obscura with a lens— in the second edition of his
Magiae naturalis, published in 1588. 5 It is extraordinary that he now
wants to announce the secret so carefully kept for a long time. There
is no doubt that Porta knew of the work of his predecessors, for he
stresses in the Preface how he had increased his knowledge extensively
by travel, by his study in many libraries, and by his personal intercourse
and correspondence with the most eminent scientists and artists.
According to an investigation by F. Paul Liesegang 0 this seemingly
contradictory statement is explained when one compares the wording
of the second edition with that of the first. One finds that Porta has
interjected the reference to the lens in the portion of the text cited
above, at the end of the first sentence in which he announces his secret,

THE HISTORY OF THE CAMERA OBSCURA 43

so that it appears that the secret refers erroneously to the lens. He
was probably so pressed for time when he made this addition that he
did not realize that thereby he injected a deceptive meaning.

Porta also occupied himself here in a more detailed manner with the
experiments to right the reversed picture by means of a mirror, and he
mentions that the light images projected on white paper could be
traced or drawn over; the usefulness of a portable camera obscura as
an aid in drawing and painting was quite evident to him.

The second edition of Porta’s Magiae naturalis was translated into
German, and this translation was published at Nuremberg (1715)
under the title Magiae naturalis, oder Hauss-, Kunst- und W under -
buck . . .

The priest Franciscus Maurolycus ( 1494-1575), a renowned teacher
of mathematics in Messina, concerned himself with the direction of
light rays in the camera obscura and states in his Pbotismi de lumine
et umbra (1575), the solution to the question which had troubled the
students of optics since Aristotle, why the image of the sun projected
into a darkened room appeared round, although the aperture through
which the rays passed was rectangular. 7

Caspar Schott also describes, in his work Magia universalis naturae
et artis (Wurzburg, 1677), the camera with and without a lens and
presents theoretical and optical comments.

THE PORTABLE CAMERA OBSCURA

In the time of Porta a whole room was usually adapted for use as
a camera obscura, but later portable cameras were manufactured.

The first mention of a small portable camera is found in the exten-
sive work of the Praemonstratensian monk Johann Zahn, devoted to
optics, Oculus artificialis teledioptricus; sive, Telescopium ex abditis
rerum naturalium et artificialium . . . adeoque telescopium (Herbipoli,
1665). Zahn describes the camera obscura which he provided with
lenses mounted in a tube; moreover, he took into consideration the
influence of focal length of the lens employed on the size and scale
of the image and gives us exact designs of his apparatus. On page 1 80
of the above-cited work he illustrates several types of cameras with
lenses and a slanting, reversible mirror. By this arrangement the image
was projected upward in perpendicular position, as in the modem
reflex camera.

Another very interesting illustration of such a portable camera

44 THE HISTORY OF THE CAMERA OBSCURA

obscura is found in a work written by the Jesuit, scholar Father
Athanasius Kircher, who was well versed in optics. This camera was
built with the object of setting it up in the open air and of facilitating
the drawing and painting of landscapes. The title of the book was
Ars magna lucis et umbrae, in X. libros digesta, quibus admirandae lucis
et umbrae in mundo, atque adeo universa natura, vires effectus, que uti
nova, ita varia novorum reconditiarumque speciminum exbibitione,
ad varios mortalium usus manduntur (Amsterdam, 1671).

Athanasius Kircher (1601-80), one of the most versatile scholars
in mathematics and natural science of his time, was born near Fulda.
He studied mathematics first at Wurzburg and later at the Jesuit
College at Rome. The first edition of his Ars magna lucis et umbrae
appeared in 1646, at Rome, and was looked upon at that time as a
masterpiece, although largely devoted to the discussion of unim-
portant matters from beginning to end. Kircher did not discover any
of the properties of light. Nevertheless, the science of optics is indebted
to him for a great deal— among other things, distinctive descriptions
and illustrations of cameras and magic lanterns (see below). Thus in
the second edition of his Ars magna, Chapter IV, p. 709, “De parastasi
per specierum in obscurum locum immissiorem,” we find described
how to copy different objects and produce a likeness. The illustration
shows an opening in the floor of the camera through which the artist
entered; also it is explained how the reversed picture of the different
objects in nature are produced on paper or canvas in the interior of
the camera obscura.

As regards the invention of the camera obscura the following appears
in The Photographic Journal (London, 1857, IV, 129): In a letter
from Sir Henry Wooton to Lord Bacon it is stated at length that the
celebrated astronomer and mathematician Johannes Kepler (1571-
1630) set up a revolving tent which had on one side a hole of about
1 ’/ 2 inches in diameter, through which he put a tube holding a convex
glass, and that he drew with a pen on paper the images projected by
this lens. Major General Waterhouse also calls attention to the writings
of Robert Boyle, who mentions in his The Systematic Cosmos or
Cosmical Qualities of Things (1669) a portable camera obscura, and
he believes that according to the language of' the passage cited the
invention should be credited to this Irish scholar {Phot. Jour., 1903,
XXXIII, 333). Zahn’s publication of his invention, however, is dated
four years earlier.

STEREOSCOPIC (BINOCULAR) VISION 45

Another portable camera obscura was described by Robert Hooke
in 1679. Marco Antonio Cellio designed in 1687 a portable camera,
which was to serve particularly for the rapid copying of copperplate
etchings, paintings, and silhouettes. Georg Busch observed in 1775
that the image in the camera obscura always reproduced nature exact
in detail, but that it was distorted by perspective.

W. Hooper, in his Rational Recreations, in Which the Principles
of Numbers and Natural Philosophy Are Clearly Elucidated (London,
1 st ed., 1755; 2d ed., which I have before me, 1782, in II, 36, Table 3)
described an original design for a camera obscura in the form of a
table with reflecting mirrors. This demonstrates how widely known and
popular, for instruction or entertainment, the various types of camera
obscura had become. Interesting details on the development of the
camera obscura are given by M. von Rohr in the Zentral-Zeitung fiir
Optic it Mechanik, 1925, XL VI, 233, 255.

The literature of that period shows conclusively that after the
camera obscura had been invented essential improvements in the opti-
cal apparatus were negligible during the seventeenth and eighteenth
centuries. Whatever modification we find during this period relates
usually to the improvements on the mechanical side of the camera.
Progress in optical apparatus seems to have come from England, where
in 1812 W. H. Wollaston made public his lens in the shape of a
meniscus and definitely stressed the importance of an exact focus.
Fifteen years later G. B. Airy published his classical work on the theory
of astigmatism for the single lens in the camera obscura.

Chapter VI. stereoscopic (binocular) vi-
sion

As early as two thousand years ago Euclid studied the phenomena
of binocular vision and enunciated the principles pertaining to them.
He demonstrated that each eye sees a slightly different image in look-
ing at an object and that it is by the union, merging or fusing together,
of these two dissimilar images that the two eyes perceive the object as
a whole, with the appearance of relief and solidity obtained in ordinary
vision. Five hundred years later the celebrated physicist and physician

4 6 THE INVENTION OF PROJECTION APPARATUS

Galen treated this subject of binocular vision more exhaustively than
had Euclid.

Leonardo da Vinci, in his treatise on painting, which was published
in Milan in 1589 from his posthumous manuscripts, indicated quite
plainly the dissimilarity of the images which each eye beholds, and he
cites this as the reason why finished paintings never give the effect of
that relief in natural objects which we perceive by binocular vision.

Jacopo Chimenti, a Florentine painter of the sixteenth century, also
concerned himself with experiments to produce stereoscopic pictures
by means of the art of drawing; such drawings by Chimenti are pre-
served in the Musee Wicar, at Lille (see Phot. Jour., April, 1862, p.
29, 1 and Bull. Soc. franc, de phot., 1922, p. 206, with table).

Porta repeats in his Magiae naturalis, in the chapter “Uber die
Strahlenbrechung” (Vols. V— VI), the propositions of Euclid and the
opinions of Galen and so fully illustrates the details of these two
theories that we recognize not only the fundamental principles but
also his anticipation of the modern stereoscope. 2 After Porta’s time the
subject of binocular vision attracted little attention, and it was not
taken up again until the first half of the nineteenth century.

Chapter VII. THE INVENTION OF PROJEC-
TION APPARATUS IN THE SEVENTEENTH CEN-
TURY

Usually, but erroneously, the Jesuit Athanasius Kircher is named
the inventor of the apparatus for projection, or magic lantern. 1

J. B. Porta is said to have projected not only images of natural objects
into his dark room by sunlight but also designs drawn on thin paper,
which were strongly illuminated by the sunlight allowed to shine
through them. At the same time he made the drawings movable, and
therefore he could give the picture any motion desired— a clever de-
vice, which must have seemed supernatural at that illiterate time. In
this manner, Porta writes, he produced to the surprise of his audience
presentations of hunting scenes, battles, and so forth. Kircher relates
that he once saw an excellent performance of the Crucifixion made by
Porta’s method, and in a similar manner the Emperor Rudolph was

THE INVENTION OF PROJECTION APPARATUS 47

entertained by his mathematicians by a procession of all the emperors,
from Julius Caesar down to himself. 2

The invention of the magic lantern as an apparatus for projection
is to be credited to the celebrated Dutch physicist Christian Huygens
(1629-95). He is noted as the founder of the undulatory theory of
light and of the theory of probabilities. He improved the telescope and
discovered the rings of Saturn. He also laid down the principle of
centrifugal force and invented, in 1656, the pendulum clock.

The earliest information about a magic lantern dates from 1656.
W e leam the fact that Christian Huygens made a magic lantern— the
oldest of which we know— from the correspondence of Huygens
with his brother Ludwig. After publishing in a previous work (D. opt.
Wochenschrift, 1919, pp. 152, 163; compare Eder’s Jahrbuch, XXX,
34) the investigations concerning the magic latern, the whole pro-
cedure is fully described in this correspondence.

This is reported by F. Paul Liesegang, writing on Christian Huygens
(at the time of the tercentenary birthday of the scholar, on April 14,
1929) and the magic lantern (“Uber Christian Huygens und die Zau-
berlateme,” in Centralztg. f. Opt. u. Mecb, 1929, L, 167).

Huygens’s attention was diverted by his many more important in-
ventions, and subsequently he paid no more attention to this trifle
(“bagatelle”). When his father, then ambassador from the Nether-
lands to the court of France, requested that he should make a magic
lantern for him, he used every pretext to avoid discharging this com-
mission. He was afraid of losing his reputation if it became known that
he had made an apparatus evidently intended for the production of
ghostly apparitions (D. opt. Wochenschrift, 1919, pp. 152, 165; VI
£1920], 337, 355; VII, 20). About 1665 the renowned scholar worked
on a device for projection, but we have no details of its construction.

Thomas Walgenstein, a Dane, who in 1658 studied at the University
of Leyden and was acquainted with Huygens, improved the magic
lantern in shape and form and introduced it commercially. We know
of demonstrations at Paris, 1662, Lyons, 1665, Rome, before 1670
(perhaps even in 1660), and later at Copenhagen, 1670. Walgenstein’s
magic lantern was fitted with a concave mirror condenser and double
lens to intensify the illumination. Huygens’s magic lantern was intro-
duced into England in 1663, in which year there is mentioned such a
lantern in use by the London optician John Reeves, who was an
acquaintance of Christian Huygens.

48 THE INVENTION OF PROJECTION APPARATUS

For an earlier description and illustration of the magic lantern with
artificial illumination, we are indebted, as stated above, to the German
Praemonstratensian monk Johann Zahn.

He described a portable projection apparatus in his above-mentioned
Oculus artificialis teledioptricus (1665, p. 256), and elucidated it by
drawings. It can be seen from these that the construction of his magic
lantern is the same as that adopted in the projection apparatus of today.

Athanasius Kircher also described the magic lantern, although some-
what later, and popularized the art of projection among wide circles,
repeating and supplementing the experiments of Porta and others by
exhibiting with his magic lantern at night and in many ways more
effectively than Porta had done by daylight.

In the second edition of his work Ars magna lucis et umbrae, 1671,
Kircher gave two illustrations of his magic lantern. 3 Kircher adds the
following description:

Make and finish a wooden box and put on it a chimney, so that the smoke
of the lamp in the box is on a level with the opening, and insert in the open-
ing a pipe or tube. This tube must contain in the front a very good lens,
but at the end of the tube, i. e., in the opening of the box (“in foramine
vero seu in fine tubi ”), it is necessary to fasten the small glass plate, on
which is painted an image in transparent water colors. Then the light of
the lamp, penetrating through the lens and through the image on the glass,
which is to be inserted, vertically, i. e., upside down) will throw an upright,
enlarged colored image on the white wall opposite. In order to increase
the strength of the light, it is necessary to place a concave mirror behind
the illuminant of the lamp.

It is obvious that in the illustration the engraver made the error of
placing the slide or small transparency outside of and in front of the
projection lens. A projection of the image would not be possible with
the slide so placed. Its proper position is behind the projection lens
and in front of the condenser.

From this fact Professor Reinhardt, to whom we owe a profound
study of the history of projection lanterns, 4 concludes that Athanasius
Kircher lacked a clear conception of the action of light rays in the
projection lantern and that probably he only saw the magic lantern
somewhere and so could not rightly claim its invention. Indeed Kircher
claims also the credit of having brought about the construction of the
magic lantern by his description, in the first edition of his Ars magna
lucis et umbrae, of the mode of operation of lenses in the optical

THE INVENTION OF PROJECTION APPARATUS 49

apparatus. In this passage, as Reinhardt was the first to point out, he
hands down to us an interesting historical note, which I have failed
to find mentioned elsewhere. Kircher narrates (p. 768 of the 2d ed.)
that, based on his description, a Danish mathematician of repute, Thomas
Walgenstein, had constructed an “improved” magic lantern and had
demonstrated it in various places in Italy. Certainly one cannot easily
recognize from Kircher’s description or illustration what the Walgen-
stein lantern looked like, but we receive a helping hand here from
another author of the seventh century.

In his work Cursus seu mundus matbematicus Claude Francois Milliet
Dechales (1st ed., 1674; 2d ed., 1690), particularly in the third volume
of the second edition (p. 696), reports that in 1665 a learned Dane
introduced at Lyons a lantern through which could be produced “at
night, from a small drawing (prototypus), a very clear image on the
wall” and that this was done, as is generally presumed, through two
lenses (that is, condenser and projecting lens) . This Dane, well known
in the history of optics, is no doubt the Thomas Walgenstein men-
tioned by Kircher. 5 It seems that Walgenstein traveled everywhere in
Europe with his magic lantern, but he never explained the inner
construction of it to the public in his demonstrations. Reinhardt believes
that this is the reason for Kircher’s fanciful picture and his haziness
about the optics of the apparatus. Dechales also includes in his work
a drawing. He describes, however, in a conclusive manner the forma-
tion of the enlarged light image. According to the drawing the object
is placed within the focal distance of the lens, 0 which forms a virtual
image and brings it to a focus within the lens system (at a diaphragm
not shown in the diagram), after which it is projected by the front
element of the projection lens in the form of an enlarged real and
inverted image on the screen. This lens tube, or barrel, could be, as
Dechales expressly emphasizes, made longer or shorter in order to
obtain a distinct and sharply defined image, regardless of the distance
between it and the projection screen. Even for that Dechales had the
proper explanation. He also discusses the effect of the mirror and the
required focal lengths of the lenses, of which the former was to be
shorter than the latter. He also showed that the flame of itself could
not produce either a correct or a reverse image, if the optical lens system
of the lantern is properly designed, and that a properly restricted disk
of light must appear on the projection screen. Only after he had dis-
covered all this by himself, Dechales relates, was he permitted by the

5 o THE INVENTION OF PROJECTION APPARATUS

inventor to view and take measurements of the interior of the lantern.

Reinhardt credits Walgenstein with the invention of the magic
lantern and the art of projection. In this, however, he went too far in
his appreciation of Walgenstein. The oldest English description of the
magic lantern is found in the book on optics by Molyneux (1692);
by that time the apparatus had already become an article of trade.

THE LAW OF REFRACTION AND THE WAVE THEORY OF LIGHT

Snellius (Willebrord Snell van Roijen), professor of mathematics
at the University of Leyden, in Holland, discovered (1626) the law
of the refraction of light and states it as follows: “The sine of the angle
of refraction is in constant exact proportion to the sine of the angle
of incidence.” That it was he, not Descartes, who discovered this law
is proved by the testimony of Huygens and others; Snellius worded
the law in his lectures somewhat differently from the present form
given to it by Descartes.

The wave theory of light was laid down by Huygens (1690) in
opposition to Newton’s (1678) emission or “corpuscular” theory.
The telescopes of that time all showed colored fringes around the
images projected from them. This chromatic aberration of lenses was
first corrected by the Englishman John Dollond (1706-61).

Dollond was a silk weaver for many years and devoted much study
to mathematics and optics. In 1758 he discovered the different behavior
of colored light rays in media of different refractive power and con-
cluded that it should be practicable to construct telescopes capable of
giving images without colored marginal fringes. In 1757 he produced
compound lenses, made of flint and crown glass, which showed no
chromatic errors (achromatic lenses). He also eliminated spherical
aberration, but all this only by means of empirical practical experi-
ments. It was not until 1814 that Fraunhofer arrived at a method of
calculating a spherically and chromatically corrected objective.

Chapter VII (REWRITTEN*) . THE INVENTION
OF PROJECTION APPARATUS

The projection apparatus developed from the magic lantern and
also the magic lantern, it is believed, came out of the earlier camera
obscura. This can be traced to an erroneous interpretation of parts of
the writings of J. B. Porta and of the Jesuit Father Caspar Schott
(1608-66) who was professor of mathematics in Wurzburg (Bavaria) .
It was the mistaken opinion that Porta in his presentations with the
camera obscura had already produced at that time transparent images. 1
Notwithstanding the close connection between both apparatus, the
development proceeded along an entirely different road, although the
magic lantern had assumed the work originally assigned to the camera
obscura, namely, the presentation of light images in a dark room.

According to the investigations of F. Paul Liesegang the magic
lantern originated from an ancient process of throwing shadows with
the aid of a mirror. 2 This was described first by Porta in 1589; but
a legend points to the fact that this method was evidently kept secret
and was known as magic art in the early ages. Writing, to be projected,
was painted on a mirror which was held against the rays of the sun
and thus reflected on the opposite wall a hazy shadow picture. Athana-
sius Kircher, in Rome, endeavored to improve the method, because
he desired to project writing at the greatest possible distance. He suc-
ceeded in this by inserting in the course of the rays, reflected in the
mirror, a condensing lens which acted as an objective and produced a
much sharper picture of the writing. Thus originated the first primi-
tive projection arrangement. Kircher described this in the first edition
of his Ars magna lucis et umbrae (1646). He used this arrangement
for the projection of figures, too, and also presented them in the
evening by candlelight.

As Kircher wrote later (2d ed. of Ars magna, 1671), there were
many who devoted themselves to the improvement of his method. A
very interesting case of the application of his method has come down
to us. In 1653 or 1654 the Jesuit Father Andreas Tacquet, in Leyden
(Belgium), arranged with Kircher’s apparatus a regular projection
presentation of a trip to China. 3 Undoubtedly by that time he was
using pictures on glass. But it was hardly possible to paint during the

‘This rewritten chapter has never before been published. The original typescript,
sent by Dr. Eder in 1933 to the translator for inclusion in the American edition, is in the
Epstean Collection, Columbia University Libraries.

52 THE INVENTION OF PROJECTION APPARATUS

presentation the series of pictures on the concave mirror. It was only a
step from this to the magic lantern.

The invention of the magic lantern as a projection lamp must be
credited to the famous Dutch physicist Christian Huygens ( 1629-95) .
He is known as the founder of the theory of undulation of light and of
the theory of probabilities. He also improved the telescope and dis-
covered the Ring of Saturn. He laid down the law of centrifugal force,
invented the pendulum clock, and designed the magic lantern, which
he had constructed by his friend Tacquet. 4

Huygens himself considered it beneath his dignity to bother further
with this “trifle,” because other more important and serious inventions
engaged his time. But he must be called the creator of the magic
lantern.

Thomas Walgenstein, a Dane, acquainted with Huygens, studied
at the University of Leyden, took up the magic lantern, and developed
it to a practical form, making it known by presentations, particularly
in France and Italy.

The earliest information about the scare lantern ( Schreckenlaterne ,
Lanterne de Peur ) of Walgenstein is found in a letter addressed by the
Parisian Petit to Huygens, in 1662.® The first publication about the
apparatus, with lengthy geometric optical details, appeared in 1668
in a little-known optical textbook Centuriae optical pars altera by the
Italian priest Francesco Eschinardi. 8 Here appears for the first time
the name “magic lantern,” which Kircher evidently gave to the appara-
tus. A more detailed description, however, is given by a sketch which
the mathematician Dechales published (1674) from a book on optics
at Lyons in 1665. 7 The illumination of the glass picture was brought
about by a large concave mirror; a condenser lens was not used. The
first lens of the double-lens objective was placed near the glass pic-
ture; the second could be moved for the purpose of sharpening the
pictures. The well-known illustration of the magic lantern furnished
by Kircher in the second edition of his Ars magna (1671) is faulty.
The tube containing the lenses of the objective is erroneously shown
between the lamp and the glass picture. 8

In Germany the magic lantern became known through Johann Chris-
toph Sturm, who was professor at the University of Altdorf, near
Nuremberg. 8 He introduced the magic lantern (1672) in his experi-
mental lectures as a novelty and gave an exact description of it in his
Collegium experimentale sive curiosum ( 1 676) . At this time the Nurem-

THE INVENTION OF PROJECTION APPARATUS 53

berg optician Franciscus Griendel exhibited for sale magic lanterns
of different sizes. 10 Joh. Zahn devoted himself exhaustively to the
magic lantern in his optical textbook Oculus artificialis teledioptricus
sive telescopium, published in Wurzburg (1685-86). Zahn and Sturm
also described projection clocks, 11 which later came into general use.

In England 11 the optician John Reeves occupied himself as early as
1663, in London, with the production of a magic lantern. In 1668 the
scientist Robert Hooke reported on a universal projection arrangement.
The first detailed publication in England was given in 1692 by
Molyneux in the book Treatise of Dioptrics. The magic lantern de-
scribed by him differs from Walgenstein’s apparatus in that it contained
a condenser lens.

Noteworthy is the later magic lantern of the Dutch professor
s’Gravesande, of Leyden, described in his Physices Elementa Mathe-
matica (1720-21). This apparatus was equipped with an oil lamp and
a four-flame burner placed in the center of curvature of a concave
mirror and had a double objective with a central diaphragm. Ehren-
berger, at Hildburghhausen (1713), occupied himself in particular
with the development of movable magic-lantern pictures.

The magic lantern served particularly for the amusement of children.
As early as 1685 Joh. Zahn proposed the use of this apparatus for
anatomical lectures, and in 1705 Creiling, at Tubingen, recommended
the light image for all educational purposes. 13 All this without success,
however. Indeed, the magic lantern fell more and more into the hands
of adventurers for the presentation of spirits with which to dupe the
superstitious. Georg Schropfer, in Leipzig, about 1770, is particularly
noted for this art. The climax of ghost projections was, however, the
phantasmagoria which Robertson presented in 1 798 in Paris and other
cities with great refinement. 14

From these phantasmagoria, which a German by the name of
Philipsthal introduced into England (1802) and which gradually lost
in their subsequent exploitations their gruesome character, developed
the famous “dissolving views,” which remained for nearly half a cen-
tury the principal exponents of the practical art of projection. 15 The
“dissolving views” method, improved particularly by the Englislunan
Childe, who perfected it first in 1839, consisted in the application of
two, three, or even more projection apparatus, which were put into
action alternately or simultaneously. Of greatest importance to this
dissolving-view equipment was the calcium light, invented in 1822 by

54 THE INVENTION OF PROJECTION APPARATUS

the London physician Gumey, 18 which, owing to its greater power
of illumination, displaced the weak oil lamp and permitted large
sensation-creating projections.

Birckbeck, in London, used calcium light for projection apparatus
in 1 8 24, 17 and in 1832 Cooper and Carry ( ? ) , in London, constructed
a projection microscope with calcium light (oxyhydrogen-micro-
scope), which Pritchard perfected in 1837 by employing a triple
condenser in a cooling vessel. Donne and Foucault introduced, at
Paris, in 1844, the art of projection and used their projection micro-
scope (“photoelectric microscope”) as a source of illumination. Fou-
cault and Duboscq, in 1849, constructed automatic projection arc
lamps. The latter perfected at that time a projection apparatus for
scientific use which remained the model for decades. In America the
art of projection was later particularly promoted by Professor Martin. 18
The essential improvement was made in the projection apparatus by
the use of an objective calculated for portrait photography by Professor
Petzval, of Vienna, in 1 840.

The projection with calcium light as well as with electric arc lights
was at that time very involved, because it was necessary to prepare
oxygen and hydrogen gases for the former, and for the latter it was
necessary to produce an electric current by means of a large battery
of galvanic lamps. Therefore, in most cases one continued to rely on
the primitive oil lamp. It was really a progressive step when optician
Marcy of Philadelphia, in 1872, replaced the oil lamp by a very prac-
tical kerosene lamp with flat wicks. 19 The “sciopticon” created a revolu-
tion in the art of projection and assisted greatly in its spread. The
method owes its large growth, however, to the electric light of modem
times, because, since the model of the 90’s, most towns were equipped
with electric power stations, in which the use of all electric arc lamps
for projection apparatus can be adequately employed. Its greatest
impetus came with the substitution of a metal wire in place of carbon
in the electric incandescent lamp and strong lamps with concentrated
filaments have been manufactured since 1912.

The episcopic projection apparatus for paper pictures was described
in its earliest primitive form by the famous mathematician Leonhard
Euler, in 1750, and they were constructed, if not then, at least a very
few years later. The invention was lost and was made anew several
times, until in 1867 Kriiss, in Hamburg, brought his wonder camera
into the market and found many sales. At the same time wonder cameras

STUDIES OF PHOTOCHEMISTRY

with calcium lights were made in both England and America. Episcopic
projection was also greatly improved by employing electric arc lamps,
of which the first practical apparatus was the epidiascope of Zeiss, in
Jena, in 1898. 20 Incandescent electric light was first employed in
1 9 1 1 by Schmidt and Haensch in their spherical episcope as well as by
Liesegang in his globoscope employing the then new strong metal
filament lamps.

Chapter VIII. studies of photochemistry

BY INVESTIGATORS OF THE SEVENTEENTH CEN-
TURY UP TO BESTUSCHEFF’S DISCOVERY IN 1725
OF THE SENSITIVITY OF IRON SALTS TO THE
LIGHT AND THE RETROGRESSION OF PROCESSES
IN DARKNESS

Natural philosophers in the seventeenth century were the first to
take up the changes caused by light in plant life. Ray was one of the
first who, in 1686, attributed the green color of leaves to the influence
of sunlight and thus called attention to the difference between the
action of light and air. 1 Other writers before Ray, like Grevius, in his
Anatomia plantarum, and Scharroc, in his Histor. propagat. vege-
tabilium . . . considered air the cause of the green color, and accord-
ing to J. Vossius, in his De lucis natura et proprietate (1662), it was
warmth which caused the vivid coloring of animals and plants in sunny
climates. 2

The fact that the bleaching of linen and other materials was greatly
hastened by light was well known to the ancients, not only to the
Greeks and Romans but also in Egypt and India. The French acade-
mician Ed. Mariotte (1666-84) made conclusive observations of the
phenomena which occur in the process. In his Traite de la nature des
couleurs (Paris, 1688) he states: “There are many yellow or dark
materials which are bleached when they are alternately dampened
and then dried in the sun. When they are then white and are left in
the light without being dampened again for a long time, they will
turn yellow.” 3

5 6 STUDIES OF PHOTOCHEMISTRY

In 1707 the French royal physician, Nicolas Lemery (1645-1715),
called attention 4 to the crystalline structure of plants growing out of
salt solutions in general. Petit notices, in 1722, that solutions of nitrate
of potash in ammonia would produce prettier vegetation in sunlight
than in the shade. 5

Count Bestuscheff (1693-1766), Lord High Chancellor and later
Field Marshal of Russia, invented, in 1725, his “Tinctura tonico-
nervina,” asserting that he employed in its production the assistance
of light. This “tincture” was formerly very highly esteemed and was
sold in Russia at a very high price as a secret remedy, because the liquid
was supposed to contain gold; later the prescription came through
a laboratory assistant into the hands of Lamotte, who sold it in France;
this is the reason this solution is also known as “Lamotte’s Gold Drops.”
The Russian Empress Catherine bought the secret from BestuschefFs
heirs and ordered the preparation of the tincture of iron to be made
public. For detailed statements of the history of this preparation see
Trommsdorff’s Journal der Pharmazie (1881, p. 60) and Kemer’s
Annalen der Chemie und Pharmazie (XXIX, 68) . BestuschefFs original
directions, as generally followed, consisted in heating iron sulphide,
sulphur, and bichloride of mercury, subliming the iron chloride formed
and allowing it to liquify and then dissolving it in four times its weight
of alcohol. This deep-yellow solution was exposed to sunlight in her-
metically closed flasks until it became colorless. (Reduction of ferric
chloride to ferrous chloride.) It was also known even then that the
solution decolorized in light and regained its yellow color in the dark
or when air had access to it.

Bestuscheff, therefore, was not only the first to discover the light
sensitiveness of iron salts and to observe the reduction of ferric to
ferrous salts, but he also recognized a light reaction which after a
while, up to a certain degree, reversed itself in the dark.

Chapter IX. phenomena of phosphores-
cence: LUMINOUS STONE; DISCOVERY OF THE
LIGHT- SENSITIVITY OF SILVER SALT; THE FIRST
PHOTOGRAPHIC PRINTING PROCESS BY SCHULZE,
1727

We learn from the writings of Aristotle and Pliny that the Greeks
and Romans knew of several substances which were luminous in the
dark. Aristotle mentions the sea, meat, and some fungi (or rotting
wood), and Pliny tells of shining precious stones. That diamonds shone
in moderate warmth was known to Albertus Magnus and probably to
others before him. 1 But it was not until the seventeenth century that
phosphorescent bodies, “the marvelous light-absorbing and light-emit-
ting luminous minerals,” were discovered. The beginning was made,
in 1602-4, by the shoemaker Casciorolo, in Bologna (Bononia), who
devoted a great deal of time to the study of alchemy and was the first
to discover that barium sulphide, which is found in the vicinity of Bo-
logna, when put between red hot coals became luminous. It was also
called “Bologna stone” or “lapis Solaris.” 2 From this time on there was
an almost maniacal zeal for making new discoveries of these luminous
minerals, which led many writers on the history of physics to observe
as Heinrich does, “One might well call the second half of the seven-
teenth century the phosphorus epoch of natural science.” Efforts
tended toward increasing the phosphorescence of those luminous
minerals which were known and to find new ones. 3 Every new dis-
covery created an enormous sensation.

Toward the end of the seventeenth century the invention of a
peculiar artificial “luminous stone,” a phosphorescent mass, materialized
by Christoph Adolph Balduin, attracted general attention. His real
name was Baldewein, and he was born in 1623, at Dobeln, near Meissen,
and died in 1682, at Grossenhain, in Saxony, where he was magistrate.

In 1674 Balduin took a different and entirely novel course from
Casciorolo. He was the first to produce calcium nitrate by a solution
of chalk in nitric acid. He realized that this salt absorbs moisture very
quickly in the open air and intended to apply this knowledge for the
marvelous alchemic purpose of imprisoning the “universal Weltgeist.”
He set out in the open air all manner of things in which to catch the
Weltgeist. He supposed that this solution of chalk in nitric acid, which

5 8 PHENOMENA OF PHOSPHORESCENCE

when dried absorbs moisture rapidly, would be of great use for this
purpose. As soon as the salt became liquid he drew off the W eltgeist
by distillation and set the residue again in the air. On one occasion it
happened by accident that everything in his glass retort, after being
highly heated, dried up, and he found that the dry matter which had
been deposited on the inner side of the retort was luminous.

This phosphorescent fused stone was variously named: “Balduin’s
luminous stone,” “Balduin’s phosphorus,” “phosphorus hermeticus,”
or “magnes luminaris” (light magnet or light sponge).

Balduin describes his luminous stone, which he called “phosphorus”
( carrier of light) , in the Miscellanea curiosa medico-physica Academiae
naturae curiosorum; sive, Ephemeridum medico-physicarum annus
quartus et quintus, 1673 and 1674 (Frankfurt and Leipzig, 1676).
In the “Appendix,” p. 167, Balduin writes of the qualities of his “phos-
phorus hermeticus,” which filled one of his friends with such enthu-
siasm that he wrote an extravagant madrigal, which we quote here.

Madrigal

The new world still would be hid Behind the sea had not the wise hero
Flavius of Cosen discovered the magic of the magnet stone and its glorious
wonders. But one thing more is wanted wherewith the voyage hard to
Colchos may be eased through further miracles. That is, Oh, Hermes’s Son,
thy fiery magnet stone, thy self-invented phosphorus that rules with radiant
light the destiny of Jason’s ship. Here sparkles another star; we progress
clear and fast and lo! from far awav we see the golden fleece!

This is written with dutiful devotion and with everlasting memory to
his highly respected friend Johann Engelhart, Medic. C.

This curious book is, in its manner and style, characteristic of the
method of writing employed by the alchemists of that time. Balduin
believed that he had discovered in his phosphorus, which glowed in
the dark, the philosopher’s stone, and renewed his efforts to improve
it, but in vain. He intended at least to help others along the road of his
discovery, and so published the supposition that his light-gatherer had
some relation to the philosopher’s stone.

Of course Balduin is quite silent in the first treatise which refers to
this matter concerning the manner and means used in the preparation
of his light-gatherer. He states only that the residue in the glass retort
in which he distilled the “alkahest” glowed after the distillation was
completed. However, the preparation of Balduin’s Leuchtstein (Bolog-
na stone) was subsequently disclosed, and very soon Kunckel von

PHENOMENA OF PHOSPHORESCENCE

Lowenstjern, Robert Boyle, Lemery, and others worked along the
same lines and described the production of this phosphorus.

The phenomena exhibited by and through these phosphorescent
minerals attracted great attention and led to the most absurd specula-
tions. Balduin even declared the moon to be a huge phosphorescent
mineral which absorbs the rays of the sun during the day and emits
them again at night time. Since these minerals were stimulated to
phosphorescence by a preceding exposure to radiation or sunlight and
emitted a fairly bright light, they were looked upon as a magnet or
a kind of sponge, which could suck up the light and give it out again,
and so forth.

The study of the phenomena of phosphorescence directed the atten-
tion of scientists to the phenomena of light. The chemist Johann
Kunckel von Lowenstjern (1638-1703), informed of Balduin’s experi-
ments, commenced new investigations and described the procedure
in such a manner 4 that “Balduin’s phosphor” could be produced with-
out any difficulty.

Some weeks after Balduin’s phosphorus had become publicly known,
Kunckel (as he writes) made a trip to Homburg and took with him
a luminous fragment of it. When he showed it there, he was told that
a bankrupt merchant, who also dabbled in medicine and was called
Dr. Brand, had also produced a material which became luminous at
night. Brand, in 1674-75, in order to repair his lost fortune, had turned
to the production of the philosopher’s stone and chemical remedies.
Among other experiments, he attempted to distil human urine by heat,
and in this manner he discovered phosphorus. After Kunckel had in-
spected the small amount of phosphorus which Brand had accidentally
obtained, he imparted the news by letter to Kraft, in Dresden. Kraft
inunediately journeyed to Homburg, without informing Kunckel,
bought Brand’s process secretly for 200 thalers, promising him that
he would not teach it to anyone. This defeated Kunckel’s attempts to
make a deal with Brand, and he departed without having learned any-
thing about Brand’s method for the production of phosphorus. But
Brand had mentioned at some time to Kunckel that he had made use
of urine in his experiments, which led Kunckel to work along these
lines, and he was fortunate enough to discover, for the second time,
the production of phosphorus. 4

The discovery of the production of phosphorus was of the greatest
importance to chemistry, but has not as yet had any reaction on photo-

6o PHENOMENA OF PHOSPHORESCENCE

chemistry. However, the studies of the phenomena of phosphorescence
shown by certain mineral compounds, especially the stimulation given
by Balduin (1675) with his Bologna stone, in conjunction with Hom-
berg’s discovery (1693) of Leuchtstein from lime and muriatic acid
gave an impetus, indirectly, to the discovery of the first photographic
processes with silver salts in the beginning of the eighteenth century.

The first description of luminous minerals was printed in Venice in
the work of Ad. Jul. Caesar la Galls: De phenomenis in orbe lunae,
(Venice, 1612). It is related there that it is not necessary to expose the
minerals to strong sunlight, for mild light would suffice (H. Kayser,
Handbuch der Spektroskopie, 1908, IV, 603; Felix Fritz, Phot. Indust.,
1925, p. 487). Another of the very earliest works on the subject was
that by Peter Poterius, Pharmacopoea spagirici (Bonon., 1622, p. 272).

Lemery, in Paris, describes Homberg’s experiments with phosphorus
minerals, many of which he contributed himself in his Corns de chymie
(9th ed., Paris, 1689). He mentions that heat is injurious to luminous
minerals, and therefore advises that they should not be exposed to
light when hot (both citations by Felix Fritz, Phot. Indust., 1925, p.

487)-

This would indicate that a heat effect, contrary and antagonistic to
the action of light, was known to exist as far as luminous minerals
are concerned. This does not apply to chemical processes, in which
heat, on the contrary, not only is not detrimental to the reaction of
light but even assists it if both act at the same time, while heat alone
in pure photochemical processes in general cannot take the place of
the action of light. But all this was unknown to the physicists of that
time; it was not until very much later that Schulze recognized the
difference between the effect of light and of the dark heat rays.

JOHANN HEINRICH SCHULZE DISCOVERS, IN 1 72 7, THE SENSITIVITY TO
LIGHT OF SILVER SALTS; EMPLOYS THEM IN THE FIRST PHOTOGRAPHIC
PROCESSES; DIFFERENTIATES DETWEEN LIGHT AND HEAT IN PHOTO-
GRAPHIC PROCESSES AND DISCOVERS PHOTOGRAPHY

I pointed out as early as 1 8 8 1 that we must consider as the first
discoverer of the sensitiveness to light of the silver salts Johann
Heinrich Schulze (born May 12, 1687, in Colbitz, in Magdeburg;
died 1 744, in Halle) . He was appointed, in 1720, professor of medicine,
and, in 1729, also professor of Greek and Arabic at the University of
Altdorf. In 1732 he was called to the University of Halle as professor

PHENOMENA OF PHOSPHORESCENCE 61

of medicine, of rhetoric, and of archaeology. In addition to all these
activities, he devoted much time to chemical experiments, attempting
to reproduce the luminous stone of Balduin. Schulze was still in
Altdorf when he occupied himself with the production of this stone.
He employed, at one time and quite by chance, nitric acid containing
nitrate of silver for dissolving chalk. When he exposed this silver
nitrous mixture of chalk and nitrous lime accidentally to light, he
discovered that silver salts were sensitive to light.

Much to his surprise he noticed that the surface of the chalky
sediment which was turned toward the light had darkened, while
the side turned away from the light remained unchanged. Schulze
continued his investigation of this phenomenon, demonstrated by
unquestionable experiments that this darkening was caused by light,
not by heat, and thus became the discoverer of the sensitiveness to
light of the silver salts. He found that the compound mentioned above
turned a violet black, “a tro-rubentem et in coeruleum vergentem”
and satisfied himself that this result must be attributed to light, not to
heat , for when he exposed the mixture in a bottle to the dark heat of
an oven, the color did not become darker. In order to make certain
whether only those parts of the silver-impregnated chalky sediment
turned dark which were directly affected by light, he tied a thin
thread from the mouth to the bottom of the bottle and observed that
the silver sediment remained white where the string kept the light
from shining on it. He also pasted paper stencils on the glass, on which
words and whole sentences were cut out. Before long those parts of
the silver sediment which were not protected from light turned dark
in the sun, and the words and the sentences were perfectly delineated
in the sediment. 5 He showed this experiment to his friends; to those
who were not familiar with the procedure it seemed very marvelous.
A mere shaking up of the sediment caused the writing produced by
light to disappear entirely, and the sediment was ready for another
light impression. Schulze also cites in his essay the observation that
sunlight concentrated through a burning glass would immediately
blacken the silver-impregnated chalk sediment and that a pure (i.e.,
not containing chalk) solution of nitrate of silver would turn dark
gradually. 6

Judging from these statements, there can be no doubt that Schulze,
as early as 1727, not only knew definitely that silver salts were sensi-
tive to light, but that he applied this knowledge to inscribe, or copy

62 PHENOMENA OF PHOSPHORESCENCE

(“inscribere”), written characters by the aid of light. It follows that
Schulze, a German, is to be credited with the invention of photography,
which was pointed out for the first time by this author. Even this phrase,
that one can “write” by the aid of light on silver salts, anticipates the
later word “photography.” Schulze’s essay was almost entirely for-
gotten or not very highly esteemed in his time, which may have been
due to the difficulty of access to the record of his work. Beccarius,
Scheele, Senebier, Davy, Heinrich, Link, and Landgrebe seem to
have known little or nothing of Schulze and his work; even Priestley,
who lived closer to the time of Schulze, while citing Schulze’s experi-
ments in his history of optics (1772), places them in an erroneous
chronological position, since he gives to Beccarius a place before
Schulze; in addition, no dates are cited by Priestley. 7 Fiedler, in his
De lucis effectibus cbemicis (1835), also falls into the same error or
anachronism. None of the modern authors seems to have known the
work of Schulze, and the present writer was the first, basing his state-
ment upon the study of the original sources, to point out the German
scientist Schulze as the inventor of photography in its first inception. 8
With Johann Heinrich Schulze, in 1727, begins a new epoch in the
history of the invention of photography.

REJECTION OF THE ERRONEOUS PRESENTATION OF SCHULZE’S MERITS
BY POTONNIEE IN HIS “HISTOIRE DE LA PHOTOGRAPH IE,” 1925

Inadequate and incorrect accounts of Schulze’s part in the invention
of photography by Potonniee must be corrected in the interest of
historical truth. Potonniee has treated the invention of the first photo-
graphic printing process by Schulze in 1727 with malicious and de-
rogatory remarks; he is silent on the fact that Schulze was the first
physicist who distinguished between the chemical action of light
and the effect of heat, although the chapter in which Potonniee deals
with this matter is headed “Chimistes et photochimie,” which would
seem to demand a correct and complete treatment of the subject.

Why does Potonniee deny Schulze’s indisputable achievement, which
can be established by documentary evidence of the silhouettes which he
copied in 1727 in sunlight and on silver-salt layers, or by the posi-
tives he made from stencils, after having made negatives of a string?
Why does he ignore the general scientific recognition, so important
to the consideration of the history of photochemistry, that here is
presented a specific photographic action of light which has no con-

PHENOMENA OF PHOSPHORESCENCE 63

nection whatever with the rays of heat and is produced as well in
direct sunlight as in reflected light? This narrow viewpoint of some
French and English authors is not in conformity with the spirit of
objective scientific and historical investigation.

Evidently Potonniee was not sufficiently acquainted with this au-
thor’s works, in which the lines are definitely drawn between the
claims of Schulze to the discovery and the inventors of new lines of
thought. Potonniee never mentions these works in his book, although
they contain conclusive documentary proof of Schulze’s priority,
which this author proved in his book Johann Heinrich Schulze, der
Lebenslauf des Erfinders des ersten photographischen Kopierverfah-
rens (1917). See also Dr. Eder’s Quellenschriften zu den friihesten
Anf'dngen der Photographie (1913), in which both the original Latin
and a German translation are given.

It is necessary here, also, to correct a misleading statement of
Hellot’s invention (1737) made by Potonniee in his Histoire, 1925.
Potonniee states that Hellot, who had invented a sympathetic ink with
silver nitrate which turned black under light, “had made his experi-
ments about the same time as Schulze”; he creates on the reader a false
impression, unfavorable to Schulze, with this statement, since in fact
Hellot did not publish his information until ten years later.

With greater fairness than Potonniee displayed and with typical
scientific objectivity, the English scholar Charles R. Gibson has ac-
knowledged in his chapters on the history of photography in the
collective work Photography as a Scientific Implement (1923) the
unquestioned merits of Schulze. Gibson writes: “Schulze’s experiment,
published in 1727, proved a real stepping-stone in the evolution of
photography . . . [even though] Schulze had no idea whatever of
making a permanent record.” Gibson states correctly that the direct
route of the invention of photography led in a straight line from
Schulze, via Wedgwood and Davy, to Talbot, who, as inventor of
modem negative photography in the camera and of the subsequent
copying process, must be called the inventor of modern photography.

Chapter. X the LIFE OE Johann heinrich

SCHULZE

HIS YOUTH AND YEARS OF STUDY

Schulze was born on May 12, 1687, in Colbitz, Grand Duchy of
Magdeburg. His father, Mathaus Schulze, supported himself and his
numerous family by tailoring and keeping bees. The preacher of that
time in the village of Colbitz had been suspended for many years and
was finally transferred to another place. In his place Andr. Albr.
Corvinus was appointed pastor. He tried diligently to improve the con-
dition of the neglected congregation, cared for the education of the
children, and visited the school as often as the inefficiency of the school-
master demanded. The bright six-year-old boy Schulze attracted the
pastor’s attention; he became fond of him and placed him under the
private tutor who taught his own children. During these private lessons
the older scholars were taught the rudiments of Latin and Greek, but
little Schulze learned only religion and calligraphy. He was very atten-
tive to the teacher’s instructions and the recitals of the scholars, and
his eager mind and precociousness helped him to grasp things quickly.
Often on leaving school he borrowed the books of his comrades in
order to learn surreptitiously by himself what others had to learn labor-
iously by public instruction. His teacher, noticing this, visited his father
in order to leam how the boy spent his time at home and found him
in a corner of the garden, behind the beehives, with a Greek New
Testament in his hands, laboring over the abbreviation of the Greek
words. When he learned of the boy’s remarkable thirst for knowledge,
he gave him a better edition of the Testament, which greatly assisted
his advancement. He had the instruction of several teachers in this
manner until he was sixteen years old, when they returned to the newly
erected Friedrich University, at Halle.

The university in Halle was founded by the Great Elector of
Brandenburg, Friedrich III, who later (1701) became Friedrich I, the
first king of Prussia; it was dedicated and opened in 1694 and named
the “Friedrichs-Universitat” after its founder. King Friedrich I be-
stowed upon this institution his special attention; his son, King Fried-
rich Wilhelm I, continued it after the death of his father (1713),
although in general he took no great interest in higher education.

At that time there lived at Glaucha, a suburb of Halle, the celebrated
pastor and professor August Hermann Francke.

Pastor Francke (born 1663, in Lubeck; died 1727, in Halle) was an

JOHANN HEINRICH SCHULZE 65

eminent philanthropist and theologian. He had spent an eventful youth.
As lecturer and teacher at the University of Leipzig (1695) he had
difficulties, owing to his lectures, which were delivered in a free-minded
though sanctimonious manner. In 1692 Francke was made professor of
Oriental languages at the University of Halle, a chair which he later
exchanged for that of theology at the same university. In the same
year he became pastor at Glaucha, which he made the center of his
endowments and bequests.

In 1 698 he erected there an orphan asylum, as well as schools for all
classes, and admitted the talented, orphaned students to the higher
institutions of learning. He added a large institute for Bible study,
named after Freiherr von Canstein, a printing establishment, a book-
seller’s shop, and a pharmacy. This Francke Foundation gradually en-
larged the scope and usefulness of its philanthropic work for all who
came under its influence.

In 1 697 Pastor Corvinus brought young Schulze to the attention of
his friend Francke, with the result that Mathaus Schulze brought his
son to Halle in that year, where Francke took the boy’s education in
hand, placing him in the Latin school attached to the orphanage.

At that time, in 1701, Salomon Negri, a very learned Arab, came
from Damascus to Halle. Francke induced him to remain there for
more than a year and teach the Arabic language in the “Oriental
College,” which Francke had founded, to the students of the university,
and to six pupils of the orphanage; Schulze was among the latter.

In 1 704, for the first time, some of the young men were sent from
the orphanage to the University at Halle. Schulze was one of them, and
he devoted himself to the study of medicine. Francke recommended
him to D. Richter, at that time physician of the Konigliche Pedago-
gium. This learned medical man had a large practice and carried on
an extensive correspondence, and he employed young Schulze, dictat-
ing letters to him and sending him to patients in order to bring him
reports of their condition; all these duties, however, were not permitted
to shorten the time allotted to him for his studies. In addition, Schulze
attended lectures by the world-renowned chemist and physician Georg
Ernst Stahl (1660-1734), who was professor of medicine at the Uni-
versity of Halle from 1694 to 1716. Schulze, introduced by Francke’s
recommendation, acquired from Stahl the first rudiments of chemistry;
he also studied under Christopher Cellarius, whose original perfectly
good German name was Keller and who was from 1693 to 1707

66 JOHANN HEINRICH SCHULZE

professor of history and rhetoric at the University of Halle. Cellarius
was the author of Liber memorialis, an elementary Latin primer which
was generally used as the basic textbook in teaching Latin until late in
the eighteenth century and which Goethe, as he relates in his Dichtung
und Wabrheit, had to memorize diligently.

After Schulze had carried on these studies for two years a friend
persuaded him to give up medicine and devote himself to the study of
theology and philology. So Schulze was transferred to the theological
school. At first he majored in philology under the guidance of Profes-
sor Michaelis, under whom he read the Bible in Hebrew; then he
studied Syrian, Chaldaic, Ethiopic, Samaritan, and Rabbinical litera-
ture, all of which connected up ingeniously with his previously acquired
knowledge of Arabic. These studies in philology were not permitted
to interfere with his work in theology and philosophy at Halle.

SCHULZE IS APPOINTED, IN 1708, TEACHER OF BOTANY, ANATOMY,
GEOGRAPHY, AND PHILOLOGY AT HALLE

In recognition of his varied and thorough scholarship, Hieronymus
Treyer, the head of the Konigliche Pedagogium, in Halle, with the
consent of Francke, offered Schulze a professorship. He taught elemen-
tary courses in botany, anatomy, Greek, Latin, Hebrew, geography,
and in the highest class “poetry and philosophy.” In 1716 Schulze
edited, on the basis of his lecture notes for the teaching of Greek, the
third edition of the Erleicbterte griechische Grammatik, by Johann
Junker, which subsequently ran into several editions. For seven years
he was active in the profession of teaching. Meanwhile, although he had
not yet made up his mind to follow medicine, he attended the lectures
of Heinrich Heinrici, then professor extraordinary for anatomy and
surgery.

SCHULZE, IN 1715, UNDER THE INFLUENCE OF THE CELEBRATED
PHYSICIAN FRIEDRICH HOFFMANN, TURNS TO MEDICAL SCIENCE

In 1712 the famous chemist Hoffmann (1660-1742), physician in
ordinary to King Friedrich I of Prussia, was called to Halle as professor
of medicine. Next to Boerhave, Hoffmann was the best-known phy-
sician of his time. Born in Halle, February 19, 1660, he studied at the
University of Jena, 1678, at Erfurt, 1679, returned to Jena, 1680,
and then made a journey to Holland and England. He went to London
and Oxford, where the studies, libraries, and pharmacies of the most

JOHANN HEINRICH SCHULZE 67

learned were opened to him; he especially attracted the good will and
friendship of the great scholar and philosopher Robert Boyle.

Hoffmann’s connection with Boyle’s pioneer work in the methods
of exact investigations into chemistry and physics is well documented.
Boyle was at that time president of the Royal Society of London, and
their association is interesting to us because Boyle was the first to
publish, in his essay Experimenta et consider ationes de coloribus
(1680), the observation that silver chloride will become dark in color
when left exposed to the air. Boyle did not attribute this change to
the action of light, but considered it as an effect of air and moisture.

Hoffmann certainly knew Boyle’s published works and would be
influenced by the course of his researches, which added so much to
the advance in natural science. He was a colleague of the chemist Stahl
at the Halle institution, from whose scientific theories he often openly
dissented. Hoffmann wrote many valuable chemical and medical
essays. Among his accomplishments, he was the first to classify mineral
waters as bitter, alkaline, and ferruginous waters and correctly to
indicate their medicinal properties. His name survives today in the
medicine he introduced— “Hoffmann’s drops,” the “Atherweingeist”
(ethyl acetate) of our present pharmacopoeia.

In all the many chemical essays by Hoffmann there is but one inci-
dental remark on the gradual darkening of a silver nitrate solution:
“particularly when it is exposed to the open air and the rays of the sun.”
Felix Fritz, who has devoted special studies to the works of Hoffmann
(Photograpbische Industrie, 1916, p. 193), tried to connect this com-
munication of Hoffmann’s with Schulze’s later discovery of the light
sensitivity of silver salts, to which we shall refer later. Hoffmann’s
remark quoted above is found in the collection of Hoffmann’s physico-
chemical observations ( Friderici Hoffmanni observationum pbysico-
chymicarum, Lib. Ill, Halle, 1722). The Latin text of the original
reads: “Argentum, ab omni contagio venero immune adeoque puris-
simum, videtur omni colore esse orbatum, sed tamen si solvitur in aqua
forti, et ejus solutio affunditur cretae, eaque solvitur, tunc amethystino
eleganti imbuitur colore, praesertim si aeri libero et radiis solaribus
exponitur. Idem color etiam fit, si solutio argenti in vase aperto paulo
diutius stet et aliquid chartae bibulae adjiciatur.” This may be trans-
lated, “Silver which is free from copper, and therefore quite pure,
is colorless, but when dissolved in aqua fortis and this solution is poured
on chalk and again dissolved, the liquid will be imbued with the color

68 JOHANN HEINRICH SCHULZE

of amethyst, especially when exposed to open air and rays of the sun.
The same color is obtained when the silver solution remains for a long
time in an open vessel and a piece of blotting paper is added.”

This would indicate that Hoffmann attributes the darkening of the
solution of silver nitrate neutralized by chalk from free nitric acid
(a solution of nitrate of silver and calcium nitrate) partly to the action
of air and partly to the sun’s rays, and he adds that the same result is
obtained, after some time, by throwing a piece of blotting paper into
the solution (even without sunlight). There is no evidence of a
scientific conception of the specific action of light on silver salts.

It seems, therefore sufficiently proved that Hoffmann in no way
influenced the subsequent discovery by Schulze of the light-sensitivity
of silver. That Hoffmann exerted a great influence on Schulze’s
education and career is unquestionable.

The author treated Hoffmann’s part in the history of photography
exhaustively in Pbotographische Industrie (1925, No. 37), while Felix
Fritz, in the same publication (1925, No. 18), places Hoffmann in
advance of Schulze, to the latter’s detriment, and attributes the dis-
covery of the light sensitivity of silver salts to Hoffmann. On this
matter the author remarks:

It is proven by documents which are still accessible that Schulze was in
no way influenced in his discoveries by the statements of Hoffmann, which
at their best were only vague; Schulze himself writes clearly that he set out
to make a “luminous stone,” from a solution of nitric acid containing silver
salts, by adding to it an excess of chalk; he set the bottle with the muddy
mixture on a window ledge, and thus observed the formation of images
by light (silhouettes and photographic prints from stencils) which resulted
from both direct and reflected sunlight.

Whether Schulze was inspired in this by Hoffmann or not is im-
material as far as the subject is concerned, but it is of consequence in
an estimate of his character. Why should Schulze keep silent on
Hoffmann’s influence, if he had been inspired by him? It certainly
would not have been honorable to hide his knowledge of earlier
experimental work, which had paved the way for him, by his fatherly
friend, teacher, and benefactor; particularly since Hoffmann taught
in a neighboring town and was in constant communication with him
on scientific subjects.

It is well to recall the method followed in the preparation of disser-
tations and learned theses in those times. A thorough knowledge of the

JOHANN HEINRICH SCHULZE 69

early literature of the subject, preferably back to classic antiquity,
was essential. All findings and conclusions from the often meager
experiments had to be traced back and built up genetically on the
works of earlier authors; a lack of familiarity with the literature of the
subject or silence on a known priority would have been severely
criticized.

All one needs to do is to look into the numerous dissertations which
were carried on under Schulze at the university to make it apparent
at once that he stressed the importance of the citation of sources.
There can be no doubt that he would have stated the fact precisely
had he recognized any connection which Hoffmann’s publication
might have had with his discovery; following Hoffmann’s experiment
he (Schulze) had found the darkening, and so forth, to be the result of
light action, which Hoffmann had not differentiated.

Schulze’s silence on Hoffmann’s experiments with the coloring of a
silver solution, which is mentioned by Fritz, is decisive proof that at
that time Hoffmann’s note was not regarded as having any reference
to the photochemical action of light, as Schulze described it.

Considering these circumstances, we come to the following con-
clusions: (1) Hoffmann made a vague observation concerning the
darkening of a silver solution, without indicating a particular action of
light; (2) Schulze probably knew of this work of his teacher; (3)
Schulze could not have regarded this work of Hoffmann as hav-
ing any connection with his own discovery of the sensitivity of
silver salts to light and their use in a photographic copying process,
otherwise the introduction to his treatise would have been worded
differently; (4) Hoffmann had no part in the discovery of the darken-
ing of silver salts by light.

THE JENA AFFAIR OF INVOKING THE DEVIL IN I 7 1 6

In 1716 Schulze was drawn into a remarkable dispute about a con-
juration of the devil in which two of the parties lost their lives. This
case created an enormous sensation, so that the theological, legal, and
medical faculties of the university interested themselves in it. It
occasioned the first independent scientific work of Schulze, then
twenty-nine years old, in the realm of medicine.

This early work of Schulze had for its background an event of
great interest in the cultural history of the country, which is known
in the literature of the Faust saga, or legend, as the Jena Christmas

70 JOHANN HEINRICH SCHULZE

Eve tragedy. On Christmas Eve, 1715, a queer trio spent the night at a
winegrower’s hut near Jena (at that time there were still vineyards in
Thuringia). They were the medical student Johann Gotthard Weber,
the shepherd Hans Friedrich Gessner, and the peasant Hans Zenner.
They proposed nothing less than to invoke or conjure up “the prince
of the realm of the sun, Och, that he produce at their behest the spirit
Nathael, who owed obedience to him, in visible and human form, so
that he might be of assistance to them in the raising of treasures.”
When the owner of the vineyard, the tailor Georg Heichler, who
was acquainted with their plans and had stipulated that part of the
treasures come to him, visited the hut the next day (Christmas), he
found Gessner and Zenner dead and Weber unconscious. On the
table was an open copy of the Clavicula Salomonis and of Dr. Faustus’s
Hdllenz'ivang, which dealt with the exorcising or conjuring up of
spirits and the ability to make the devil subservient. On the roof of the
hut had been drawn a circle together with all kinds of magic symbols.
There could be no doubt: Satan, whom the three bold men had conjured
up, had appeared in person and had departed, taking with him their
souls. The student Weber, who recovered shortly, was arrested, while
the bodies of the two peasants, escorted by two executioner’s assis-
tants, were publicly carried on a hangman’s dray through the town
to the gallows and there buried in the presence of a great number of
people. For final judgment the legal documents of the case were sent
to the University of Leipzig. The theological, legal, and medical
faculties of the University of Leipzig declared, in their unanimous
opinion, delivered in April, 1716, that death was not caused by any
supernatural agency, but was brought about by the fumes of the
charcoal which the peasants, in order to keep warm on that cold
December night, had lighted in a pot, the remains of which were found
by the court commission. Nevertheless, the student Weber was dis-
missed from the University of Jena and exiled from the country,
because “contrary to his baptismal vows, by which he renounced the
devil and all his works, he had dealings with and placed his faith in
the devil’s black art and so had profaned the honor of God.”

The incident created great popular excitement, and many were
inclined to regard the affair as a direct influence of the devil. For
that reason Hoffman, Schulze’s teacher, published a small dissertation,
entitled Ernes beriibmten Medici griindlicbes Bedenken und pbysi-
kaliscbe Anmerkungen von dem todtlicben Dampf derer Holtz-

JOHANN HEINRICH SCHULZE 71

Kohlen, auf V eranlassung der in Jena beym Ausgang des 1715 Jabres
vorgefallenen traurigen Begebenbeit. Now, Hoffmann had more than
ten years earlier published a dissertation De diaboli potentia in corpora
(Halle, 1703; 2d ed., 1712), which in no way denied the domination
of the devil in the material world. Thereupon followed a long con-
troversy. Friedrich Andreas Erdmann, a practicing physician at Jena,
asserted in his Griindlicher Gegensatz auff das Griindliche Bedencken
und phy sikalische Anmerckungen von dem todtlichen Dampfe der
Holtz-Kohlen that the death of the two peasants must by all means
be attributed to Satan. Schulze published a new edition of this polemical
pamphlet, with a Preface and comments by himself in which he de-
fended the opinions of his teacher Hoffmann. It bore the title Erdmann,
Friedrich Andrea, Griindlicher sogenannter Gegensatz auff das in Halle
herausgegebene griindliche Bedencken von dem todtlichen Dampf
der Holtz-Kohlen mit Anmerckungen von Johann Heinrich Schulzen
(Halle, 1716). However, it was a long time before the last word was
written in this controversy; as he dealt with his predecessors, so it
happened to him: a third reprinted Schulze’s Preface and comments
under the title C. A. T. Med. Cult. Unpartheyische Priifung der
Vorrede und kurtzen Anmerckungen Herrn Johann Heinrich Schult-
zens endeavored to maintain that in some cases even results that can
be explained by natural causes must be attributed to evil spirits and their
extraordinary powers and that the incident at Jena “was largely
attributable to Satan’s power over bodily matter.” This controversy
dragged along until 1720, with new pamphleteers constantly entering,
but Schulze successfully maintained his point, and it was acknowledged
finally that the charcoal fumes (carbonic oxide poisoning) were the
cause of death of those who had conjured up the devil. Throughout
this controversy Schulze played a strong and meritorious role, de-
fending the viewpoint of science with great skill and the depth of his
convictions, based on his thorough knowledge of chemistry and
medicine, against ignorance and superstition, never a light task.

SCHULZE ATTAINS HIS DOCTORATE AT HALLE IN 1 7 I 7
AND BECOMES PROFESSOR AT ALTDORF, I72O

Schulze received the degree of Doctor after writing the thesis
Dissertatio inauguralis de athletis veterum, eorum diaeta et habitu,
dealing with the physical training and diet of boxers and prize fighters
(athletes) of early times. In the year that Schulze received his doctorate

72 JOHANN HEINRICH SCHULZE

and his Venia legendi (license to teach) in Halle, he left Hoffmann’s
house. His lectures on physiology, anatomy, history of medicine and
chemistry were attended by large audiences, but had scarcely started
when disturbances arose at the university which caused him to lose all
but five of his students. These disturbances interfered greatly with the
lectures, and many students abandoned their classes at the university
and left Halle.

Some of his students, when taking their departure, advised Schulze
to move to Altdorf, and they probably caused his being called there
several years later. After the loss of most of his students he held private
lectures and devoted himself to writing books, especially since the
bookseller Johann Christ. Francke had founded a new Halle publishing
house. He also collaborated with other scholars on the V ermischte
und abgesonderte akademische Bibliothek.

In June, 1719, he married Johanna Sophie, daughter of the above-
mentioned Pastor Corvinus, and when Professor Heister left Altdorf,
in 1720, for Helmstedt, Schulze was appointed his successor at the
University of Altdorf, in the district of Nuremberg.

The University of Altdorf attained high repute and sent out many
famous men. Gottfried Wilhelm Leibnitz, the celebrated scholar and
philosopher, who subsequently founded the academies of sciences at
Berlin and St. Petersburg, held debates in Altdorf and attained his
doctorate there. In 1806 the imperial city of Nuremburg, with its
surrounding territory, was ceded to Bavaria, and the University of
Altdorf was merged with the University of Erlangen in 1809. The
history of the University of Altdorf was written by Will in a mono-
graph published at Altdorf (1808).

Schulze commenced his lectures at Altdorf on anatomy and surgery,
on Dec. 13, 1720, with a discourse relating to the subject of his
teaching, a correct survey of anatomical studies.

In the following year he delivered there his first academic lecture
on the history of anatomy. The title reads; “Historiae anatomicae
specimen primum.” The excellent scholarship shown in it was the
occasion of his admission to the Imperial Leopold-Caroline German
Academy of Natural Sciences in 1720. This academy was accustomed
to bestow upon its initiates an epithet, selected from the world of
classical antiquity. Schulze received the surname “Alcmaon” after
one of Pythagoras’s pupils. Alcmaon (about 500 b.c.) belonged to the
school of medicine founded by Pythagoras and because of his dis-

JOHANN HEINRICH SCHULZE 73

coveries in the domain of anatomy and physiology he occupied a very
important place in the history of medicine among the old Greeks.
In the caption to the oldest known portrait of Schulze, the surname
“Alcmaon” is included. The appreciation with which the above-men-
tioned study of the history of anatomy was received in professional
circles induced Schulze to write an elaborate work on the history of
medicine, which was published several years later (1728) in Leipzig.
He also dealt with the study of applied medicine, published several
dissertations, and lectured diligently and with success on anatomy and
pharmacology. He engaged his pupils in practical anatomical studies,
which seemed particularly curious to his contemporaries, since the
dissection of human bodies was rarely undertaken at that time. There-
fore a public announcement of the dissection of a male or female body
at the university was an event to which attention was called by
printed invitations. In the bibliography printed at the end of Dr.
Eder’s book /. H. Schulze (1917) several such announcements of post-
mortem examinations by Schulze are cited.

He also conducted chemical experiments along the lines and in the
spirit of Stahl and Hoffmann. It was one of these experiments which
led him, in 1727, to the discovery of the sensitivity of silver salts to
light and thus to the discovery of photography.

DISCOVERY OF PHOTOGRAPHY BY SCHULZE, AT ALTDORF, 1 7 2 7

In 1725 Schulze commenced experiments for the production of
phosphorescent or luminous minerals and bodies, which he concluded
in 1 7 2 7 and published in the Acta physico-medica Academiae Caesareae
Leopoldino-Carolinae Naturae Curiosorum exhibentia Ephemerides
(Nuremberg, 1727). Schulze relates in this memoir that he found
something quite different from what he expected. He remarks: “often
we discover by accident what we could scarcely have found by inten-
tion or design.” At the outset he intended to produce the artificial lu-
minous stone of the alchemist Balduin by bringing calcium nitrate to a
red heat. Balduin, who had invented this luminous stone in 1 674, was
a member of the Imperial Leopold-Caroline German Academy of
Natural Sciences. Schulze, who was a member of the same academy and
was familiar with Balduin’s writings, aimed to produce the luminous
stone by himself.

He searched for a luminous stone which absorbs light from the
rays of the sun and so becomes luminous, but instead he discovered a

74 JOHANN HEINRICH SCHULZE

mixture which becomes darkened by the sun; that is why he called
the light-sensitive silver-impregnated mixture a “carrier of darkness”
(Dunkelheitstrager; Latin, scotophorus), which he had discovered
instead of the sought-for phosphor “carrier of light” (Lichttrager;
Latin, phosphorus). Schulze expressed this very concisely in the title
of his memoir relating to this subject, as follows: “Scotophorus pro
phosphoro inventus; seu, Experimentum curiosum de effectu radiorum
solarium” published in Acta physico-medica Academiae Caesareae
Leopoldino-Carolinae Naturae Curiosorum exhibentia Ephemerides
(Nuremberg, 1727).

The author published the complete original Latin text, together with
a faithful German translation (Halle, 1913). The particular passage
of Schulze’s memoir that is especially important for the history of the
invention as far as it concerns the identification of the action of the
sun’s rays and the lack of action of the strong heat of an open fire on
the darkening of the silver impregnated paste reads as follows:

Such aqua fords (diluted nitric acid), containing a very moderate quan-
tity of silver particles, was used by me for moistening the chalk, as required
by Balduin’s experiment. I carried on this work by an open window, which
admitted the brightest sunshine. I was astonished at the change in color of
the surface to deep red inclining toward violet blue. But I wondered still
more, when I saw that the part of the dish which was turned away from
the sun did not take on any color whatever.

Having noticed this phenomenon, I regarded it worthy of further in-
vestigation. I discontinued my work with Balduin’s phosphorus and con-
centrated my attention upon the so-called “scotophor” experiment, in order
to clear up the causes underlying the change in color. Doubtful what pro-
cedure to follow, I divided the saturated chalky mass into two parts, of
which I put one part into a long tube, such as is customarily used for com-
pounding medicines and, in order to make it easier to pour this doughy
mass into the tube, I added more dilute nitric acid. This, however, caused
too violent ebullition, and the chalk began to dissolve; in order to check
this vehement reaction, I added water. I then put the tube down in a place
where the sun shone brightly. In a few minutes I noticed that the solution
showed a similar change in color, namely, deep red, tending toward a shade
of blue, on that side of the tube which was turned toward the sunlight. The
residue in the dish I left exposed to the sunshine until it was entirely dried
up. During this period I observed that the surface became colored and
remained so for several days, until the residue was exhausted in further
experiments.

I placed this new experiment before my friends, in order to learn their

JOHANN HEINRICH SCHULZE 75

opinion; some of them thought that the change of color was due to the
effect of heat. At first we held the tube so close to the glowing fire that
it became more than sufficiently warm. But we placed it so that the part
which was previously not reached by the sunlight and had remained un-
colored, was now turned toward the fire. We confirmed the fact that there
was no change of color, although the tube had become so hot from the fire
that it was almost impossible to hold it in the hand.

This was sufficient to demonstrate that heat played no part in the change;
I therefore pass over the other experiments made along these lines. But
for the purpose of assuring myself and to be able to prove to others that
it is not heat but sunlight which brought about this deep color, I shook up
the precipitate of chalk in the tube until it was thoroughly mixed with
the supernatant water, so that the mixture showed no difference in color
in any of its parts. Then, dividing the liquid, if I may be permitted so to
call the mixture, I filled a glass with one part and put it in a dark spot
where no sunlight could reach it, while I kept the remaining portion for
further experiments. I exposed the first portion to sunlight, suspending
a thin string perpendicularly from the mouth of the center of the glass, so
that the part exposed to the sun was divided almost in half, and left it
exposed for hours to the strongest sunlight, undisturbed and untouched in
any way. When we returned to inspect it, we found the liquid thoroughly
imbued with the color. When the string was slowly withdrawn, we noticed
to our delight that the part covered by the string showed the same color
as the back of the glass which was not reached by the sunlight; we tested
the same result with horsehair, with human hair, and with a very fine
silver wire; so that there was no doubt that the change of color resulted
solely from sunlight, and that it was not in any way dependent on warmth,
not even the heat of the sun.

I began further experiments in reverse. Whenever I intended to make a
new test by mixing and shaking the solution well in order to restore to it
a colorless state, I covered the larger part of the glass with opaque bodies
or patterns which permitted the light access to only a small portion of the
vessel’s contents. In this manner I frequently wrote names and whole
sentences on paper and carefully cut out with a very sharp knife the parts
covered with ink. The paper perforated in this manner I fastened with wax
on the bottle. Before long one could see the sun’s rays write through the
perforations in the paper, through which they could reach the glass, these
very words and sentences on the chalky sediment. The light wrote so
plainly and exactly that those not familiar with the experiment were
tempted to attribute the matter to I know not what kind of trick or dodge.

In addition, Schulze determined by a counter experiment that pure
calcium nitrate is not sensitive to light by itself, that on the contrary

7 6 JOHANN HEINRICH SCHULZE

it was the particles of silver which the solution contained that caused
the phenomenon. He found that magnesia, burnt hartshorn, or similar
substances could be substituted for chalk-

Schulze also mentioned that sunlight reflected from a mirroi or
from a white wall caused the color to darken and that the action of
sunlight discussed above was much more rapid when a convex burning
glass was focused on it. Finally, Schulze expressed the opinon “that
his experiment could be applied in the examination of minerals and
metals, to ascertain whether they contain any silver, because up to
now this phenomenon had not been observed when other metals or
minerals were tested in the same manner,” and he continues “I do not
doubt that this experiment will lead chemists to other means of appli-
cation and use.”

Considering the chemical side of Schulze’s experiment, we are able
to determine exactly the composition of his light-sensitive compound
by following his supplementary directions. It was not easy at that
time to procure pure nitric acid free of chlorine, which was used as
a solvent for the separation of silver from gold. It was customary to
dissolve a small quantity of silver in nitric acid, allow the deposit of
silver chloride to settle, and pour off the clear solution of nitric acid
which contained some silver. If this acid mixture is poured on calcium
carbonate or magnesium carbonate, the nitric acid will then be neu-
tralized through the formation of calcium or magnesium carbonate,
whereupon the excess chalk, through partial metastasis (double de-
composition) forms some silver carbonate as a white precipitate,
which settles from the silver nitrate solution and which, similar to
silver chloride, darkens in the light. However, since Schulze diluted
the liquid with ordinary well water, which always contains some
chloride, chloride of silver was also formed in this experiment. From
this we must conclude that Schulze’s light-sensitive mixture, which
he used either as a paste or dry, was made up of chloride or carbonate
and of nitrate of silver, together with an excess of white chalk or
magnesia. This substance, just as in our modem printing-out paper,
for example, a silver chloride emulsion on a substratum of white baryta,
serves as a white background, thus considerably enhancing the clear vis-
ibility of the color change during the light reaction and the legibility
of the design so obtained. Schulze was also aware of the fact that one
could intensify the photographic action of light on silver salts by means
of optical instruments, particularly by convex condensing lenses.

JOHANN HEINRICH SCHULZE 77

Because of these facts Schulze must be declared without doubt
the inventor of photography with silver salts. He is also the first
scholar in natural sciences who drew a sharp and distinct line between
the peculiar chemical action of light rays as compared with the effect
of heat rays and confirmed his views by experiments.

SCHULZE DECIPHERS THE CHARACTERS ON THE CORONATION
ROBE OF THE GERMAN EMPERORS

In 1728 Schulze, who was deeply versed in the Arabic language,
received a copy of the inscription of the age-old coronation robe of
the German emperors. This inscription was supposed to be in unknown
Oriental characters, because they could not be correctly deciphered
at that time. Schulze recognized that the writing in question was of
Coptic origin (old Arabic decorative), and he succeeded in deciphering
them, although not quite correctly.

The coronation robe of the German emperors was kept, in Schulze’s
time, together with the other imperial insignia, in the city of Nurem-
berg, and is at present preserved in the former imperial treasure chamber
at Vienna; it is an extremely valuable treasure. The mantle, richly
embroidered with gold and pearls, was added to the imperial regalia
on the passing of the last of the line of Hohenstaufens. The lining is
silk woven and dyed with purple; on top is a gold clasp. The edge
is bordered with three rows of pearls and bears the Coptic inscription
mentioned. The Nuremberg patrician Hieronymus Wilhelm von
Weber became interested in these gold embroidered characters, had
exact copies made of them, and showed them to different scholars,
among whom was Schulze. He recognized that he had to deal with
an Arabic inscription written in the Coptic manner and that the hand-
work was an expensive example of Sicilian-Arabic art. He furnished
a translation which on the whole was fairly correct, although a hundred
years later it was much improved. He gave the date of the production
of the mantle as a.d. 1126, while later investigations fixed the date
as 1133— surely a matter of small importance. Expensive festival garb
such as this was made at the Saracen court in Palermo and was worn by
emirs and caliphs on holidays at court ceremonies. After the defeat of
the Saracens of Sicily, the Saracenic industry which flourished at
Palermo was taken under the special protection of the Norman kings.
Thus the highly artistic and elaborate coronation robe made in Palermo
by the Saracenic art embroiderers for Roger II, king of Sicily, came

78 JOHANN HEINRICH SCHULZE

then into the possession of the German emperors and was worn by
them as early as the first half of the thirteenth century at the corona-
tion ceremonies.

schulze’s activities at altdorf as professor of medicine

AND OF GREEK AND ARABIC LANGUAGES

Schulze wrote, in 1727, in addition to his memoir on the light
sensitivity of silver salts, many other essays which were published by
the Imperial Leopold-Caroline German Academy of Natural Sciences,
as well as various dissertations relating to medicine. Subsequently he
gave little attention to physical and chemical research, but turned with
all his energy to anatomy and surgery.

The first part of his Historia medicinae a rerum initio . . . (Leipzig)
appeared in 1728. This basic study of the history of medicine in
antiquity, which had reached only to the time when the science of
medicine was transplanted to Rome, was unfortunately never com-
pleted; it was regarded as the first scientific history of medicine. In 1729
Schulze was appointed to the chair of Greek at the University of
Altdorf. Finally, after the departure of Zeltner from Altdorf, Schulze
also added the teaching of Arabic to his other lectures, which probably
had never before been connected with the science of medicine at any
university.

SCHULZE CALLED TO THE UNIVERSITY OF HALLE IN I 732,

WHERE H E TAUGHT UNTIL HIS DEATH

A vacancy existed at the University of Halle when Nikolaus Hier-
onymus Gundling died, in 1729, who since 1708, as successor to the
celebrated Cellarius, had held the chair of rhetoric and archaeology
and since 1712 also lectured on jurisprudence. But it was three years
after Gundling’s death before Schulze, in 1732, was called to the Uni-
versity of Halle as professor of medicine and philosophy. His salary
was five hundred thalers, of which one hundred thalers were to be paid
from the funds of the university and four hundred thalers from the
Royal Prussian Treasury. Unfortunately, Schulze seems to have quite
neglected the remunerative practice of medicine and, having fallen
in debt to the extent of about one hundred thalers, he feared that his
creditors might prevent him from leaving Altdorf. When King Fried-
rich Wilhelm I of Prussia learned of this, he granted Schulze a loan for
the payment of his debts in addition to the traveling expenses to which
he was entitled; the larger part of this debt was later remitted.

JOHANN HEINRICH SCHULZE 79

This indicates the great confidence which the king had in Schulze,
for Friedrich Wilhelm I was well known as excessively parsimonious;
he reduced the salaries of many state employees and the remuneration
of a minister down to two thousand thalers.

It is this economical trend of the king that makes it so remarkable
that he helped Schulze in his financial embarrassment, probably only
temporary, and enabled him to enter on his duties at Halle.

In the list of the university courses for the years 1732 to 1736 the
only lectures announced as by Schulze are on early literature. His
Latin lectures were not very well attended, which caused him to re-
duce his activities in this branch of philosophy. On the other hand,
his lectures on archaeology attracted a great many students; this led
him to the study of numismatics, when in 1734 a student presented
him with a well-preserved tetradrachma Thasiorum, an old Greek
four drachma coin. This study stimulated him to investigate not only
everything he could discover concerning these Thasian coins, but to
consult all the literature bearing on the subject. The first fruit of this
study was a dissertation: De nummis Thasiorum (1737).

While engaged in this special study, his collection of coins grew
considerably, numbering two thousand in four years, and soon after,
three thousand. He used this important collection often in his lectures
on archaeology and stressed their importance in the historical studies
of all times. In 1738 we find him giving a special course of lectures on
numismatics.

In recognition of his numerous and outstanding scientific works
Schulze was elected a member of the Imperial Leopold-Caroline
German Academy of Natural Sciences and the Royal Prussian Society
of Scientists at Berlin, which was presided over by Leibnitz, and the
Imperial Russian Academy of Sciences, of St. Petersburg.

Schulze’s reputation as a scholar of Oriental languages and the his-
tory of art grew in importance, owing to his numerous and learned
works on these subjects; he had also gathered around him a circle of
earnest students who devoted themselves to these branches of know-
ledge. Among the names of these pupils of Schulze shines out one which
was celebrated later in the realm of the history of art as one of its
pioneers, Johann Joachim Winckelmann (1717-68). He entered the
University of Halle at Easter, 1738, and at once became one of the
most eager of Schulze’s hearers. It was Schulze who introduced
Winckelmann into scientific circles. This student of archaeology

80 JOHANN HEINRICH SCHULZE

later became celebrated for his studies of ancient art and its history
and is considered the founder of this branch of science.

Schulze continued his studies in the history of medicine among the
ancient Greeks and Romans and published a concise textbook Com-
pendium historiae medicinae a rerum initio ad excessum Hadriani
Augusti (Halle, 1742) and Dissertationum academicarum ad medi-
cinam ejusque historiam perbinentium (fasc. i, Halle, 1743).

After Hoffmann’s death, in 1 742, Schulze joined the medical faculty,
where he tried to continue the life work of his great master. He con-
tributed a biography of Hoffmann to the Geneva edition of his works,
but this is not identical with the Commentarius de vita Friderici Hoff-
manni, mentioned earlier in this chapter.

Schulze often held debates on scientific subjects and supervised the
academic theses of those who studied for the doctor’s degree in medi-
cine; he took part in nearly one hundred of these debates, over which
he presided.

He constantly studied, read, wrote, worked, and taught, retiring
more and more to his study. He became estranged from society, oc-
cupied himself in teaching and with his books rather than with his
patients, and soon renounced all gains from his medical practice. He
preferred to live on the modest income from his professorship so that
he could devote himself entirely to his scientific researches and collec-
tions. He overworked, however, and his health was weakened to such
an extent that he had to be led home from an inaugural debate, in
which he participated as the dean of the faculty. After this incident
he withdrew from the staff and sought to regain his health by taking
the iron baths at the neighboring town of Lauchstadt, in Merseburg.
His illness, however, had progressed too far, and Schulze died October
1 o, 1 744, aged 57 years, deeply mourned by the scientific world, by
the students of the university, and by his family.

Hirsch, in his Biographisches Lexicon der hervorragenden Arzte
aller Zeiten und Volker (1887, Vol. V), mentions the fact that after
Schulze’s death a commemorative medal was coined in honor of his
memory. This medal has become very rare, and none is in the collection
of the University of Halle or at the Imperial Leopold-Caroline German
Academy of Natural Sciences. There is, however, a cast of it in lead,
preserved at Vienna in the large collection of medals of great medical
men, which, gathered by Sanitatsrat Dr. J. Brettauer, in Trieste, was
left in his will to the University of Vienna, under the title: Medi-
cina in nummis.

JOHANN HEINRICH SCHULZE 81

Schulze’s library, which was very comprehensive and valuable, was
sold at public auction in May, 1745, by his heirs; the introduction to
the catalogue of the auction was written by Jakob Baumgarten, a
friend of the Schulze family.

Schulze had spent a part of his professor’s salary on his library and
on his hobby of collecting coins and medals, and he left, besides a
number of manuscripts, a very valuable numismatic collection. This
was sold to Privy Councillor Eichel by the heirs for about two
thousand thalers. The collection finally reached the University of
Halle, where it served as the nucleus of the larger collection now in
the archaeological museum of that university.

Among the papers found in Schulze’s estate is a complete work on
subjects of chemistry, which was to serve as an introduction to the
study of chemistry, with special consideration of medicine, and is of
great interest to us. The manuscript carries the title “Chemische Ver-
suche.” It was edited by Strumpff a year after Schulze’s death and was
published by the printing office of the Halle orphanage.

Schulze made extensive use in this booklet Chemische V ersuche of
the customary signs and symbols used by chemists, physicians, and
pharmacists in the first half of the eighteenth century; these symbols
had originated with the alchemists and had undergone many variations
(see J. M. Eder, Quellenschriften z u den frith esten Anfdngen der
Photographic, 1913, p. 51). At the end of the book Schulze gives a
list of the signs used, knowledge of which is quite necessary to the
reader of the booklet.

This work attracted favorable attention and went through several
editions. The first edition appeared in Halle, 1 745 ; the second, in 1757.
In this book Schulze again referred with emphasis to his scotophorus
experiment.

Below is a copy of the title in the original text of the first edition,
which is dated 1745, not 1746, as Fritz erroneously mentions. An ex-
ample of this very old and rare edition is in the library of the Univer-
sity of Erlangen, whose management kindly sent it to the author for
inspection. The title page reads: D. Job. Heinr. Schulzens/'weiland
der Artzney-Kunst, wie auch der/Beredsamkeit, Alterthitmer und
Welt-Weis-/heit Professorius auf der Konigl. Preussischen Univer-
sitdt Halle, /Mitglieds der Kay serlichen-Carolinischen, Russi-/schen,
und Konigl. Preussischen Societaten/der Wissenschafften/Chemische/
V ersuche /nach dem eigenhandi gen/ Manuscript des Herrn Verfassers/

82 JOHANN HEINRICH SCHULZE

zum Druck befordert/durch/D. Christoph Carl Strumpff. /Halle, /in
Verlegung des W ay senhauses, 1745.

Strumpff states in the Preface that he “attended to the printing,
according to the handwritten manuscript of the author, of blessed
memory, without making the slightest change.” Schulze intended, in
his Chemische Versuche, to present a guide and aid to the teaching
of chemistry, and he based his view on the phlogiston theory of Stahl.
He described the salts, antimony, mercury, and other metals, acids,
and so forth. In this work Schulze states, in paragraph 148, that raw
nitric acid could be purified of its chlorine contents by dissolving some
silver in it and this would form a white sediment (silver chloride) ; if
the clear nitric acid was then poured off, it would still contain, Schulze
says, some silver (silver nitrate), but it will be then quite adapted for
the separation of silver from gold; he called nitric acid solution “prazi-
pitiertes Scheidewasser” (water of separation or separating solvent).

In paragraph 151 Schulze refers with emphasis to his discovery in
1727 of the sensitiveness of silver salts to light, which we translate as
closely as possible in the words of the original text:

Par. 1 5 1. When dissolved silver touches the skin, wood, or bone and
they are placed in sunlight, a black color forms. One can dilute the pre-
cipitate aq. fort, (separating solvent) in ordinary water, then mix it with
chalk and expose it to the rays of the sun, so the change of color will show
visibly, during which two things are noticeable. 1. That this is not effected
by heat, because even the strongest kitchen fire works no change in color.
2. That the sun’s rays do this not only when they fall upon it directly, but
also when they are thrown upon it through a mirror or even from a
white wall.

This scotophorus experiment seems very serious to my eye. At least it
serves for a handy proof that sunlight as light has an action which is in-
dependent of its warmth, on which, as far as I know, the physicists have
not reflected up to now.

The passage cited above is of great interest in that it demonstrates
once more that Schulze recognized the value of his discovery. As
far as Schulze’s claim to priority in the discovery of the light-sensi-
tivity of silver salts and the development of photography are concerned,
this statement contained in the posthumous publication in 1745 is,
however, of lesser importance than his first original communication
concerning the scotophorus experiment in 1727, because the first men-
tioned merely confirms, eighteen years later, his previous discovery.

RESEARCH IN THE 18TH CENTURY 83

Schulze’s publication of the scotophorus experiment, in 1 727, secures
for him the priority of the discovery of the sensitiveness to light of
silver salts, and of the invention of photography in its first beginning
or original conception. His continual repetition and reiteration of it
in his posthumous Chemische Versuche proves that Schulze was fully
aware of its importance. Physicists neglected this for many years, and
it was not until the end of the nineteenth century that rights to
priority of the invention were accorded to this celebrated German
scholar.

In Dr. Eder’s Johann Heinrich Schulze (1917) can be found elab-
orate literary proofs, a complete list of Schulze’s writings, several por-
traits of him, and facsimile reproductions of handwritten letters.

Chapter XL photochemical research in

THE EIGHTEENTH CENTURY UNTIL BECCARIUS
AND BONZIUS (1757), TOGETHER WITH A DIGRES-
SION ON THE KNOWLEDGE AT THAT TIME OF THE
INSTABILITY OF COLORS

About this time— certainly before 1737— the first observation, as far
as I can discover, of the light sensitivity of mercury salts was published
by Professor Kaspar Neumann (1683-1737), at Berlin. I quote from
his posthumous works on chemistry, 1 where he states, “It is worth con-
sidering that mercury dulcis (calomel) becomes black in the sun.” He
does not seem to have followed up this change effected by light, since
he merely mentions, in discussing silver solutions, that they blacken
the skin, without stating that light action has any part in it.

In Neumann’s day every pharmacist and chemist was familiar with
the preparation of calomel by sublimation, by mixing mercury with
corrosive sublimate, as well as its behavior when heated— that it remains
white and then volatilizes, but never turns black under heat. Therefore,
there is no room for misunderstanding when Neumann remarks that
the blackening of calomel in the sun deserves consideration. He meant
to convey to the chemists of his time that he had found something
new and noteworthy, and his statement leaves no doubt about his
recognition of the particular action of light on this mercury compound.

84 RESEARCH IN THE 18TH CENTURY

HELLOT APPLIES, IN 1 7 37, NITRATE OF SILVER TO PAPER
AND USES CHLORIDE OF GOLD FOR SYMPATHETIC INK

In 1737 Jean Hellot (1685-17 66) communicated to the Academie
des Sciences de Paris, of which he was a member, a paper giving his
experiments with a new sympathetic ink. In his study of the chemical
basis of sympathetic ink, he found that cobalt salts were used in the
production of invisible writing (on paper), which, when heated, be-
came blue or green, and disappeared gradually after cooling; he also
observed (1737) the change of color of nitrate of silver as well as of
chloride of gold on paper, when exposed to sunlight. He published
this experiment, Sur une nouvelle encre sympatbique, and informs us
that characters written or drawn on white paper with a dilute solution
of chloride of gold became, after a few hours, quite deep violet (“violet
fonce presque noir”) when placed in the air. (He does not say “in
light.”) When, however, he enclosed this prepared paper in a metal
box, the writing did not appear even after several months had elapsed;
but after that it became gradually visible. It is of great historical value
that he also referred to the use of a dilute silver nitrate solution. Writ-
ing on white paper with such a solution was invisible and did not
become apparent until after three or four months when the paper was
enclosed in a metal box, but it appeared in the course of an hour, in a
sort of slate color, when the paper was placed in the sun.

It was Hellot who points out for the first time that paper coated
with silver nitrate remains white in the dark, but turns deep grey
after an hour’s exposure to sunlight; also, that such paper, even in the
dark, undergoes a gradual decomposition and its color deepens in the
process. While this remark is correct, the explanation given for it offers
very little satisfaction. Hellot presumed that the sun merely promoted
the evaporation of nitric acid, which always contains some sulphur,
and for this reason the silver becomes dark after the evaporation of the
nitric acid, because silver is blackened by all sulphur compounds. 2

While Hellot, therefore, must be credited with the discovery of the
sensitivity to light of paper treated with silver nitrate, he had no idea
of any other use for it than to produce secret writing. The idea of pro-
ducing an image made up of light and shade in the sense of a photo-
graphic silver formation never dawned upon him.

THE ACTION OF LIGHT ON COLORED SUBSTANCES

The property of light to effect a decomposition of colored fabrics

RESEARCH IN THE 18TH CENTURY 85

was dealt with by Captain Dufay (1698-1739) in the Memoirs of the
Paris Academy in 1737:

Among the examples which I could cite is one that I wish to mention, of
a crimson colored taffeta curtain which hung for a long time before a
window; all parts which had hung exactly opposite the windowpanes were
entirely decolorized, while those parts opposite the window frame were
not bleached nearly so much. In addition, it was quite evident that in the
parts which were decolorized the silk was destroyed, and in those parts
the silk was very much more apt to tear; while in the other portions one had
to exert the usual force to tear them. 3

It is obvious that the early painters must also have gathered many
experiences about the change of colors through light. This is sup-
ported by a dissertation of Heraclius which comes down to us from
the middle of the thirteenth century, Von den Far ben und Kunsten
der Romer. He mentions various organic dyestuffs among the paints
used by artists, 4 such as madder lake, litmus, dragon’s blood, carmine,
gum of Brasilwood, lac of violets, and in Cennino Cennini’s book
Buch von der Kunst; oder, T raktat der Malereif which was published
as early as the middle of the fifteenth century, we find, indeed, a warn-
ing against the use of dragon blood: “let it stand, do not worry too
much about it.” In regard to shellac it is said that “air was its enemy”;
of saffron, “See to it that it is not exposed in the open air, as it then
quickly loses its color.” Michael Angelo Buonarotti Biondo no longer
quotes any of the mentioned vegetable colors 8 besides lac and indigo
in his T raktat von der bochedlen Malerei ( 1 549) , when he enumerates
the colors commonly used in painting. Further explanations on this
subject are given in the French work by the Jesuit Father Castel
(1688-1757), published in 1740 and translated into German in 1747
(Halle): Die auf lauter Erfahrungen gegriindete Farbenoptik.

There it is stated, on page 127:

1 know a painter whose taste and ability in painting portraits I value highly.
He showed me his palette, where he had few colors, and he told me that
he used neither carmine nor lac nor cinnabar for his red, nor did he use a
fresh yellow; but he used for blue and green only prussian blue, and for
all red and violet he used a brown red with a certain yellow of medium
quality, the name of which I have forgotten.

Referring to the custom of well-known painters of those times of
permitting red and green to predominate in their paintings. We read
on p. 128:

He, the aforesaid painter, called my attention, however, to those that are

86 RESEARCH IN THE 18TH CENTURY

stable and permanent. These colors (the yellow and the red) are false . . .
He added that lake, carmine, cinnabar and other very conspicuous colors
had not enough body, nor were they permanent, and that he who used
them in his work did not think of posterity.

Castel writes of gamboge on p. 97: “Painters do not think much of
it, because the color is not sufficiently permanent.”

That Castel realized the bleaching action of the sun is shown by the
citation, p. 171: “What is called linen is bleached by air, by sun, by
dew and by lye. The same thing happens with wax, wool, and many
other things.”

Castel was so throughly convinced of the extraordinarily great force
of light that he was moved to express himself in words which seem to
me rather daring for a Jesuit Father of the eighteenth century, p. 169:
For, God, who is pure light without an addition of darkness, was and
existed as himself before all things were created. Whereas all things were
created by that light and in it have their being, they have their origin from
light and therefore from God, who has created light: their bodies and
shapes, however, come straight from the darkness, because they are com-
posed of matter; matter in itself is dark and lifeless.

About the nature of the action of light the physicists of those days
had a very vague idea. For instance, J. J. Scheuchzer (1672-1733), pro-
fessor of mathematics and physics at the Gymnasium of Zurich and
academician, wrote in his Physica; oder, Natur r wissenschaft (1st ed.,
1703; 4th ed., 1743), from the latter edition we quote here, Chapter
XXVIII, p. 239, on the bleaching of colored stuffs:

From frequent washing and drying linen becomes white in sunlight, be-
cause wetting it causes all kinds of impurities to be absorbed by the water,
which are driven away together with the water through the small inter-
stices of the linen, which necessarily makes the linen cleaner and whiter,
because of the ensuing loss of the earthly impurities clinging to the linen.
The vivid and bright colors of silk and taffeta are easily lost in the open
air and still sooner in the sun, by which, as it is commonly said, they are
extracted, in fact, that is what happens, so that through the powerful
action of the sun’s rays the smallest color particles which cling to the
threads of silk or of other materials are in time bleached out, so that
broadly speaking they are, in a way, scraped off.

BECCARIUS DESCRIBES THE SENSITIVENESS OF SILVER
CHLORIDE TO LIGHT, 1 757

The work of Reaumur and Duhamel called forth new investigations

RESEARCH IN THE 18TH CENTURY 87

by the Italian physicist Giacomo Battista Beccaria. He wrote in Latin
and always signed himself “Beccarius.” His work is important to the
history of photography, owing to his discovery of the sensitiveness of
chloride of silver to light. Born in Mondovi, Italy, in 1716, Beccarius
was a member of a religious order, taught rhetoric and philosophy at
Rome and Palermo and physics at the University of Turin from 1748
until his death there, in 1781. He interested himself almost entirely in
the study of artificial and atmospheric electricity. Benjamin Franklin
esteemed the work of Beccarius so highly that he had an English edition
of it published, Treatise on Artificial Electricity , tr. from the Italian
(London, 1766). Beccarius also participated in the surveying in Pied-
mont, where he proved in 1774 the influence of the Alps on the devi-
ation of the pendulum. Among his physical investigations we find some
on the action of light on various substances, and in 1757 one about the
effect on chloride of silver. This essay is printed in the original Latin
text and with a German translation in the author’s Quellenschriften
zu den friihesten Anfangen der Photographie (1913), in which there
is reproduced a picture of Beccarius.

The dissertations of Beccarius and Bonzius, which were published
at the same time by the Academy of Sciences of Bologna, have the
common title which reads in translation, “On the art, which light pos-
sesses of itself, of changing not only the colors, but also the structure
of things, sometimes without detriment to the colors. 7

To Beccarius (Beccaria) belongs the priority of discovery with
respect to the light sensitivity of silver chloride. Freshly precipitated
hornsilver (cerargyrite, Ag Cl.), he states, is white; but gradually it
becomes almost violet blue. A specimen kept in a glass turned blue
only on the side toward the light, but the opposite side was still
whitish; it also turned violet, however, when one gave the glass a half
turn. This convinced him that it was the light, not the air, as he pre-
viously believed, which had effected the change of color. In order to
convince himself finally, he covered the side of the glass which was
turned toward the window and the light with a strip of black paper.
The next day he found that the parts on which the light could shine
were violet; those, however, covered by the paper were still whitish.
The procedure of Beccarius’s experiment seems quite analogous to
that of Schulze, which the latter employed thirty years earlier in his
experiment with “kreidehaltigen Silvermagna” (chalky mass saturated
with silver).

RESEARCH IN THE 18TH CENTURY

Evidently Beccarius was not acquainted with Schulze’s works, or
he would probably have mentioned them. He expressed the opinion
that there resided in light a certain force which could change colors.
He determined that it was not air, but light which blackened silver
chloride, and further stated that one must have a thorough knowledge
of the three causes, light, air, and heat, in order to study the change
of colors.

In order to appreciate Beccarius’s publication to its full extent, it is
necessary to consider the significance of chloride of silver in com-
parison with Schulze’s silver-salts sludge and with the silver nitrate
paper of Hellot, since modem photography is built on the light sen-
sitivity of silver halide compounds.

CHANGES OF PIGMENTS BY LIGHT

Bonzius carried out various experiments on the action of light on
colored ribbons, and so forth, which he published at the same time
that Beccarius published his. We learn from Bonzius’s experiments
that many colors are greatly changed by light, regardless of the effect
of heat or air. When different-colored ribbons were exposed to the
rays of the sun for several days, the violets faded first, then the rose
colors, and lastly blue and green. In the dark, in a much higher tem-
perature than that of the sun’s rays, the colors remained unchanged;
although they lost their brilliancy, Bonzius concluded that air did
not contribute anything to the change, because the bleaching pro-
ceeded just as well in an air-tight receptacle. Light from torches focused
through a burning glass had no effect. The supposition that sunlight
merely destroyed the colored particles was disproved by Bonzius’s
experiment, in which he placed the ribbons on white paper before
exposing them to sunlight. The colors faded on both sides, but no
particles remained on the paper in the place from which the ribbons
were removed.

That this last-mentioned experiment, which may seem to us super-
fluous, was nevertheless quite necessary is shown by the following
passage in A. D. Richter’s Lehr buck einer^iirSchulen fasslichen Natur-
lehre (Leipzig, 1769), where on p. 1 34, referring to dyeing, it is taught:
“Those materials which are so coarse in their pigments that they can-
not penetrate the spaces between the fibers of the fabric give color
which will not last and which will easily fade away in the open air
and sunlight.” Even J. Bischoff utters a similar crude conception in

FROM “GIPHANTIE” TO SCHEELE 89

his V ersuche einer Geschichte der Farberkunst (1780), although Bon-
zius long ago had disproved this theory. Anticipating the chronologi-
cal sequence, we should note here that Bischoff declares that only
those colored materials were genuine which could be exposed for
twelve days to air, rain, and sunshine without suffering a noticeable
change. These are requirements which are quite justified.

Supplementing this chapter, as it were, we feel inclined to add some
remarks on the degree of knowledge at that time concerning the
changes which artists’ colors underwent.

Pernety states in his work, published 1760, in Paris, Dictionnaire
portatif de peinture, that many colors are very impermanent; thus,
“Dutch pink” disappears in a short time, especially when the painting
is freely exposed to the air or to sunlight; prussian blue turns greenish
in time; colombium lac changes gradually; cinnabar does not last in
the open air (!) and “fine lac” (?) (madder) behaves similarly. We
must conclude that they were pretty well aware of the alterability of
vegetable pigments and had observed the influence of light on the
process of decomposition.

Chapter XII. FROM “GIPHANTIE” (1761) TO
SCHEELE (1777)

Tiphaigne de la Roche wrote, in 1760, a work, Giphantie, which is
“a view of what has passed, what is now passing, and during the present
century, what will pass in the world.” The transposed letters of his
name formed the word in the title “Giphantie.” It contains certain fan-
ciful allusions to the possibility of producing photographic images and
provoked even very recently a great deal of discussion. These chimer-
ical dreams were greatly admired, owing to their genius. We observe
here basically the same fantastic ideas which we found expressed a
thousand years earlier by the Roman poet Statius. We can place no
more value upon these than on the modern imaginative novels of Jules
Verne, based on the natural sciences. Tiphaigne, probably using the dis-
coveries of Schulze or Beccaria, which could hardly have remained un-
known to him, enlarged them into this fantastic tale, employing the
alchemic jargon of the time. This fantastic tale and the satirical writings
were taken altogether too seriously, because the sources from which he

FROM “GIPHANTEE” TO SCHEELE

obviously drew his information were not then known. It was there-
fore assumed that in his book the first appearance of an original idea,
namely, the production of images by light, was met.

Mayer and Pierson lay considerable stress on this Gipbantie in their
work La Photographie consideree comrne art et comme industrie, his-
toire de sa decouverte, ses progres, ses applications— son avenir (Paris,
1862). The following quotation from Gipbantie is taken from the
English translation, published 1761:

You know that the rays of light, reflected from different bodies, produce
an image and that the objects appear delineated on all polished surfaces,
as on the retina of the eye, in water and on mirrors. The elementary spirits
have studied how to fix these fugitive images. They have composed a most
subtle substance which is very viscous and prepared so as to dry quickly
and harden; by the help of which a picture is produced in a few moments.
They coat a piece of canvas with this stuff and hold it before the objects
which they wish to depict. The first result apparent on the canvas is ex-
actly that of a mirror, all objects, near or far, from which the light can
throw a picture, are seen on it. But what the mirror cannot do, the canvas
does by fixing the images by means of its sticky coating. While the mirror
reproduces for us the objects faithfully, it retains none; our canvases repro-
duce them no less faithfully, but also hold them permanently. This impres-
sion of the images is the work of the first moment they are received on the
canvas, which is immediately carried away into a dark place. An hour
later the viscous coating has dried, and you have a painting which is the
more precious, because no art can attain its reality and time cannot damage
it in any way. We take from their purest source, in the luminous bodies,
the colors which painters must extract from different materials, which
time never leaves unchanged. The faithful rendering of the design, the
truth of expression, the strokes of the brush more or less strong, the grada-
tions of shading, the rules of perspective— all these we leave to nature, who,
with a sure and never-erring hand, paints pictures on our canvas which
deceive the eye and make one’s reason to doubt, whether the so-called real
objects are not phantoms of the imagination which deceive not only eyes,
ears, and feelings, but all the senses together .... The elementary spirit
then entered upon some physical discussions: first, on the nature of the
glutinous matter which intercepts the rays and retains them; second, on the
difficulties of its preparation and use; third, on the struggle between the
rays of light and this dried substance; three problems which I submit to
the physicists of my time and leave to their discernment.

When we turn again to serious works on the subject, we find an
interesting description of the action of light in the work of Jos. Fr.

FROM “GIPHANTIE” TO SCHEELE

Meyer, an apothecary in Osnabruck (1705-65), Chymische Versuche
zur naheren Erkenntnis des ungeldschten Kalches, der elastischen
elektrischen Materie, des allerreinsten Feuerwesens und der urspriing-
lichen allgemeinen Sdure (Hannover-Leipzig, 1764). In this work (ch.
xx, p.119) Meyer investigates “what causticum is and of what it is com-
posed,” and the opinion is expressed that the corrosive mordant in lime
and other caustic substances consists of pure fire particles. He con-
tinues:

that the fiery part of the caustic might be the substance of light, which
perhaps could be made more plausible by a few not unknown experi-
ences ... a greyish-black color is acquired by the precipitated Luna
cornea when it is placed in the sunlight in a tightly closed glass. If one
causes a solution of mercury in sulphuric acid to become crystallized, this
“vitriolum mercurii” will turn black in the sun even in a closed vessel; the
white sublimate which results from the solution, when it is finally separated
by a strong fire, will also turn black in the sun.

These changes of color by light are contrasted by Meyer with those
which nitrate of silver and calomel undergo when limewater is poured
over them and both become black. Then he concludes: “the substance
of the light penetrates the transparent glass and darkens these (i.e., the
light-sensitive matter) just as the causticum does.” It is, of course,
quite unnecessary to emphasize that the blackening of the above-men-
tioned chemical compounds by limewater is to be attributed to an
entirely different cause than the blackening by light, namely, the for-
mation of silver oxide and mercurous oxide, and that it is a mere coinci-
dence that the product in both cases is blackish. This view, erroneous as
it is, is at any rate original and represents one of the earliest theories of
the chemical action of light.

From these remarks of Meyer it is evident that a knowledge of the
instability of silver and mercury salts had been pretty generally dis-
seminated before 1764. It also seems to follow that photochemical
decomposition of mercurous sulphate was known before Meyer; I did
not succeed, however, in finding an earlier reference to this subject.

LEWIS MENTIONS ( I 763 ) THE APPLICATION OF SILVER NITRATE IN THE

PRODUCTION OF DESIGNS ON BONE, MARBLE AND WHITE AGATE, WITH-
OUT MENTIONING HIS PREDECESSORS; HE FORMS THE CONNECTING LINK

with wedgwood’s experiments

Curiously enough, we encounter as early as the sixties of the eight-
eenth century a practical use of silver nitrate for producing draw-

FROM “GIPHANTIE” TO SCHEELE

ings on all kinds of objects and for dyeing hair with the assistance of
the sun. Dr. William Lewis writes, in his “History of Colors,” Part 6
of his Commercium pbilosophico-technicum (London, 1763):

A solution of silver in aqua fords, of itself colorless as water, dropped upon
white bone or other like animal substances, produces at first no stain. In
some time, sooner or later according as the subject is more or less exposed
to the sun and air, the part moistened with the liquid becomes first of a
reddish or purplish color, which by degrees changes into a brown, and at
length deepens to a black.

Lewis made his experiments entirely according to the methods fol-
lowed in the earlier efforts of Homberg and Schulze. Consequently,
it seems as if Lewis would not have any special claim to having shared
in the advancement of photography, if it were not for the peculiar
accident that his writings came into the possession of the Wedgwood
family. Their attention was called through this for the first time to
the possibility of the production of light images. Charles R. Gibson
points out, in the collective work already mentioned, Photography
as a Scientific Implement:

We have seen that Dr. William Lewis (1763) repeated Schulze’s experi-
ments and extended them to ivory and wood. It so happened that upon the
death of Dr. Lewis (1781), his notebooks relating to these experiments
were bought by the famous English potter, Josiah Wedgwood, who also
took Dr. Lewis’s assistant into his own service as secretary and chemical
assistant.

This secretary, whose name was Chisholm, seems to have acted also as
tutor to Wedgwood’s young son, Tom, who was delicate and who devel-
oped a liking for chemical experiments.

Young Thomas Wedgwood would doubtless receive much inspiration
from the scientific friends who gathered at his father’s house among whom
was Dr. Joseph Priestley ....

There is no doubt that young Thomas Wedgwood would hear of
Schulze’s experiments in connection with some of the discussions at the
meeting . . . for Dr. Priestley was conversant with Schulze’s experiments,
which he described in his History . . . of Discoveries, Relating to Vision,
Light and Colours. Then there were also Dr. Lewis’s notebooks, which were
in Wedgwood’s house, also the tuition from Lewis’s assistant, so that there is
a real link between the work of Schulze and that of Thomas Wedgwood.

This idea fell upon fertile ground with young Thomas Wedgwood,
because it led him to the well-known work with Davy (1802) with
which we shall deal later in detail.

FROM “GIPHANTIE” TO SCHEELE

Some photochemical notes by Johann Gottschalk Wallerius in his
Chemia pbysica (1765, Vol. II, chap, xxv, par. 4) deal quite exhaus-
tively with silver salts. 1 J. G. Wallerius (1709-85) was profesor of
chemistry at Upsala. Among other things, he relates that hair is black-
ened by silver nitrate and that it is very difficult to wash away the black
dye. He used silver nitrate to draw on marble, agate, jasper, and so
forth, and also employed a dilute silver solution (aqua graeca) to turn
red hair black. 1 Wallerius was acquainted with Schulze’s investigations
and quotes him with the words “Scotophoricum Schultzii.” He re-
peated his experiments, but with chloride of silver, in which, however,
he was anticipated by Beccarius (1757). Wallerius, therefore, con-
tributed nothing new to the history of photography.

WORKS OF MARGGRAF ( 1 77 I ) , PRIESTLEY, AND INGENHOUSZ, WHO IN

1786 DISCOVERED THE DECOMPOSITION OF CARBONIC ACID BY PLANTS

IN SUNLIGHT

In 1771 Marggraf mentions, in the Memoir es de Berlin (1771, p. 3),
that a red lac produced from a decoction made from dyer’s madder
(rubia tinctoria) in alum and potassium carbonate is much more per-
manent and does not fade so easily as that made from “Femambuk”
(Brazilwood). 2 In 1771 and 1772 the influence of Priestley made itself
felt in the development of photochemistry. This great scholar pre-
sented in his History and Present State of Discoveries Relating to
Vision, Light and Colours (1772) 3 the first comprehensive description
of the chemical action of light; it was, however, not complete, refer-
ring only to Duhamel, Beccarius, Schulze, and Bonzius. There is no
separate chapter devoted to this subject; for it is only mentioned in a
description of chemical actions in the second chapter of the sixth
period, “On the Bolognian Phosphorous.” Priestley concluded from
the observations at his command:

The view that light is a real substance, consisting of particles of matter
emitted from luminous bodies, is farther favored by those experiments
which demonstrate that the color, and inward texture of some bodies are
changed, in consequence of their being exposed to light. The first observa-
tion of this kind appears to have been made by Duhamel, who found that
the juice of a certain shell fish in Provence contracted a fine purple color
when it was exposed to the light of the sun, and that the stronger the light,
the more splendid the color.

As early as 1774 4 Priestley had observed that the green matter of

FROM “GIPHANTIE” TO SCHEELE

plants was developed out of carbon dioxide, without, however, recog-
nizing the part played by light in this change of color, that is, that
sunlight is necessary for the decomposition of carbonic acid in plants.
This was first observed by Ingenhousz in 1786.

Jan Ingenhousz (1730-99), a Dutch physician who was for some
years physician-in-ordinary at the imperial court in Vienna, spent his
last years in England. The work of this scholar is of the greatest impor-
tance because of his discovery that the green plant liberates oxygen
in sunlight and absorbs carbonic acid (carbon dioxide), which it gives
off in the shade— the breathing of plants. He is the real founder of
plant physiology. Until the most recent times Horace Benedict de
Saussure ( 1 740-99) was called the discoverer of the breathing of plants.
However, the work of Ingenhousz, in which he pointed out the breath-
ing of plants in light, had appeared a year before Saussure’s publication
on this subject. Only very much later did the discovery of Ingenhousz
obtain the recognition it deserved. We are indebted to him also for
important physical investigations and various pieces of scientific ap-
paratus which are described by Julius Wiesner in Jan Ingenhousz:
sein Leben und W er ken als Naturforscher und Arzt (1905).

Wiesner explains why Ingenhousz’s work was not properly appre-
ciated until so late. Influenced by Senebier, Saussure never gave him
(Ingenhousz) proper credit; on the contrary, in his writings Senebier
is overestimated, to Ingenhousz’s disadvantage. Later writers, especially
Liebig, used Saussure as their source of information, and thus it is
easily understood why before the last third of the nineteenth century
this scholar was not justly dealt with until Julius Sachse called atten-
tion to the great importance of his work.

HOOPER PLAGIARIZES SCHULZE IN I 774

When Hooper published his Rational Recreations, in Which the
Principles of Numbers and Natural Philosophy Are Elucidated by a
Series of Easy, Entertaining and Interesting Experiments (editions
1774, 1775, 1787, 1794), he gave as “Recreation XLIII” (IV, 143) a
method of “writing on glass by the rays of the sun,” which runs as
follows:

Dissolve chalk in aqua fortis to the consistence of honey, and add 10 that a
strong solution of silver. Keep this liquor in a glass decanter well stoppered,
then cut out from a paper the letters you would have appear, and paste
the paper on the decanter, which you are to place in the sun, in such a

FROM “GIPHANTIE” TO SCHEELE 95

manner that its rays may pass through the spaces cut out of the paper,
and fall on the surface of the liquor. The part of the glass through which
the rays pass will turn black, and that under the paper will remain white.
You must observe not to move the bottle during the time of the operation.

Doubtless many readers of this apparently popular work, not famil-
iar with the literature of the subject, believed that in this “Recreation
XLIII” Hooper offered something new and original. As the description
of the method shows, however, Hooper plainly plagiarizes Schulze’s
famous experiment of 1727, as described in his memoir “Scotophorous
pro phosphoro.” Possibly he was inspired by or took his information
from the account given by Priestley, a year or two earlier, of the
Schulze experiments. The credulity of those modern writers who
ascribe priority to Hooper may be dismissed without comment.

BERGMAN DISCOVERS THE LIGHT SENSITIVENESS OF SULPHATE AND
OXALATE SILVER AS WELL AS MERCURY OXALATE ( I 776)

Torbern Olof Bergman, the successor of Wallerius at the University
of Upsala (1735-84), published in 1776 the results of his experiments
on oxalic acid obtained by oxidation of sugar, in a pamphlet entitled
De acido sacchari. Here is mentioned for the first time the sensitivity
to light of metal oxalates; he describes his observation that sunlight
will turn black the difficultly soluble white powder (hydrargyrus
saccharatus), as precipitated by means of oxalic acid from a solution
of mercury in sulphuric or nitric acid. 5 We are also indebted to
Bergman for the observation that silver sulphate and silver oxalate
darken in light.

Bergman’s complete observations on related subjects are collected
in his work Opuscula physica et chemica 6 ( 1 7 79) . He states: “The rays
of the sun darken the oxalate of silver.” He goes on to describe how
mercuric oxide with oxalic acid forms a “salty white powder which
hardly dissolves and which turns black in sunlight.” He obtained the
same salt by precipitation from mercuric sulphate or mercuric nitrate
by oxalic acid, and he noticed that the mixture of oxalic acid and
mercuric chloride is sensitive to light. “Also by this method (addition
of oxalic acid to the solution) the sublimate forms a powder, which
only slightly and slowly will turn dark in the sun.” This statement
was afterward much more clearly defined by Plante (1815), but Berg-
man is, at any rate, to be credited with the discovery of the light-
sensitiveness of numerous compounds of oxalic acid.

9 6 FROM “GIPHANTIE” TO SCHEELE

He was acquainted with silver sulphate and knew that it blackened
more slowly than chloride of silver: “A solution of silver in nitric acid
will give a white precipitate when sulphuric or hydrochloric acid is
added. In the first case, however, the particles precipitated will not
cohere so well, remain grainy rather than flaky, and will not darken
as quickly. Bergman adapted his ideas on the nature of light to the
phlogiston theory. The following passage characterizes this more
closely:

It is well known that plants droop and lose their color, but when exposed
to sunlight they soon recover. Because light consists of a matter of heat
with an excess of phlogiston . . . unequal results must form, according
to the different positions of the plants in respect to light, and their vary-
ing capability to decompose light and heat.

SCHEELE RECOGNIZES ( 1 777) THE REACTION OF SILVER CHLORIDE IN
LIGHT; HE INTRODUCES THE PRISMATIC SOLAR SPECTRUM FOR THE
INVESTIGATION OF COLOR SENSITIVENESS AND DISCOVERS THAT AM-
MONIA IS AN AGENT FOR SEPARATING SILVER CHLORIDE AND METALLIC
SILVER FROM PHOTOCHLORIDE

Basing his work directly on Schulze’s investigations that were pub-
lished in 1727, the eminent Swedish chemist Carl Wilhelm Scheele
wrote his famous dissertation: Aeris atque ignis examen chemicum 1
(1777, p. 62), which is of the greatest importance to the history of
photochemistry.

Scheele (bom 1742, at Stralsund; died 1786, at Koping) started as
apothecary’s assistant in Gothenburg, and worked later in Malmo,
Stockholm, and Upsala. He came to Koping in 1775 as manager of
the pharmacy there, and bought it in 1777. He spent his time untir-
ingly on broadening his knowledge of chemistry, notwithstanding
the very modest resources at his command. The science of chemistry is
indebted to him for many very important discoveries. He discovered
oxygen independently of Priestley and Lavoisier, also many other
organic substances (oxalic acid, citric acid, malic acid, gallic acid,
glycerine), and extended the knowledge of inorganic chemistry, for
instance, by the discovery of molybdic acid and tungstic acid; he was
the first to prepare hydrofluoric acid and to isolate chlorine, which he
described as dephlogistonized hydrochloric acid, and so forth. For our
purpose Scheele’s works in photochemistry, particularly those on
silver chloride, are of special interest.

FROM “GIPHANTIE” TO SCHEELE

Scheele’s experiments on the chemical action of light, as described
in his book mentioned above, are often cited, and this much more
frequently, because the beginning of photochemistry is ascribed to
him. 8 1 have endeavored to throw light on this subject, proving that this
is an error, since there were a considerable number of photochemical
processes known before his time. At any rate, he is undoubtedly en-
titled to recognition for his services in carrying out his experiments
in a more systematic and clear-sighted manner than his predecessors.
He must also be credited with having originated the chemical concep-
tion of the reaction of silver chloride to light and the photochemistry
of the solar spectrum. He made his experiments for the purpose of
demonstrating that light is composed of and contains phlogiston. He
found that silver oxide, gold oxide, and mercurous oxide, when in the
focus of a burning glass, are superficially changed to metal (take up
phlogiston) ; he adds that heat probably plays a role in this. Scheele
also observed that nitric acid will turn red in sunlight in three hours,
while in dark heat it would take four weeks. 0

Scheele gave us the first definite statements on the photochemistry
of silver chloride and used silver chloride paper in his experiments.
He knew the different reactions of silver chloride. He recognized the
difference in behavior of silver chloride blackened by light, and the
unchanged silver chloride with respect to ammonia. This gave us the
knowledge of a fixative for silver chloride images, which unfortunate-
ly remained unnoticed for many decades.

On chloride of silver Scheele expresses himself as follows:

I precipitated a solution of silver by means of ammonia chloride . . . the
white dry precipitate turned superficially black in sunlight .... Then,
I poured some caustic spirit of ammonia on this black-looking powder and
put it aside for digestion. This liquor dissolved a good deal of the chloride
of silver, but a velvet-black powder remained. The washed powder was
largely taken up in pure nitric acid, which volatilizes in this way 10 Con-

sequently, the black substance which results from light action on silver
chloride is nothing but reduced silver.

He verified that chloride of silver remained unchanged in the dark.
It did not escape the keen observation of this ingenious chemist that
during the blackening of chloride of silver “in light, muriatic acid”
must form. “Since, however, no silver can combine in metallic form
with muriatic acid, it follows that as many single particles of the silver
chloride as are changed on their surfaces to silver, so much muriatic

98 FROM “GIPHANTIE” TO SCHEELE

acid must also separate.” He also noted that washed silver chloride,
when exposed to light under water, will give off muriatic acid to the
water; he adds that it will remain unchanged in sunlight when sub-
merged in nitric acid. He noticed that after two weeks particles of
metal separated from a solution of chloride of gold. 11

Scheele first sprinkled powdered chloride of silver on paper and
allowed the solar spectrum to act on it. He found that the silver chloride
blackened much more easily in the violet of the spectrum than in the
other colors, “because the silver chalk liberated the phlogiston sooner
from the violet light than from any other rays.” 12

If he painted a glass black and put silver chloride into the glass and
exposed it to sunlight, it did not turn black, although the glass became
quite hot. Heat rays alone, for example, those of a fire, did not succeed
in producing the blackening even after two months.

These phenomena he explained by assuming that light is probably
not pure phlogiston (principium inflammabile), but contains phlog-
iston along with heat as a constituent, and this combines with the
“silver chalk.” According to this view, light was decomposed by silver
chloride— not, as it is expressed today, the silver chloride by light— and
by this, one of the constituents is withdrawn from the light. This view
coincided with the spirit of Newton’s theory of emission, which was
prevalent at that time and was used by Scheele in connection with
the phlogiston theory.

And so we can trace manifestly the history of the development of
the beginnings of photography directly from Schulze (1727) through
Beccaria (1757) to Scheele, and we find in paragraph 60 of Scheele’s
writings (1777), mentioned above, the indubitable evidence:

It is known that the solution of silver in nitric acid, when poured on a
piece of chalk and when exposed to sunlight, turns black. The same result
is obtained, but more slowly, by sunlight reflected from a white wall.
Heat, however, without light, produces no change whatever in this mix-
ture. Could it be that this black pigment is real silver?

Based on his later experiments he answered this question in the affirma-
tive.

Richard Kirwan, who added some explanatory notes to Forster’s
English translation of Scheele’s work, expressed grave doubts regard-
ing the opinion that light consisted of phlogiston and fire and gave as
his reason “that combustible matter ordinarily does not penetrate solid
matter as does light; that, on the other hand, light does not reduce

FROM PRIESTLEY TO SENEBIER

generally metal oxides or manganese dioxide.” Richard Kirwan, F.R.S.,
was one of the most brilliant and versatile of the Irish men of science
and the author of several reputable works: On Phlogiston and on the
Constitution of Acids, Geological Essays, and so forth. Kirwan in-
clined more to the view that the light sprang from a strong motion of
the elementary fire, whereby the combustible matter was expelled
from the objects exposed to light, for instance: “drive out the light
combustible matter from the muriatic acid in chloride of silver, which
combines with silver oxide” (i Chemical Observations and Experiments
on Air and Fire, by Carl Wilhelm Scheele, with Introduction by
Torbern Bergman; translated from the German by J. R. Forster,
F.R.S., with notes by Richard Kirwan, F.R.S., with a letter to him
from Joseph Priestley, F.R.S., 1780. Also in extract by Crell, in Neueste
Entdeckungen in der Chemie, 1782, V, 231).

Chapter XIII. FROM PRIESTLEY (1777) TO SE-
NEBIER (1782); TOGETHER WITH AN EXCURSION
INTO THE APPLICATION MADE IN THOSE DAYS OF
LIGHT-SENSITIVE COMPOUNDS TO MAGIC ARTS

During the latter half of the century in which Scheele made his
experiments on the photochemical action of light (1727), the English-
man Joseph Priestley (1733-1804), occupied himself in investigating
the causes of the spontaneous reddening of nitric acid. He described
his experiments later in great detail. 1 The results of his tests demon-
strated that nitric acid turned red slowly, but more quickly in sunlight,
and kept its color unchanged after several days in the dark, even
though subjected to a considerable degree of heat. Since Priestley was
a zealous partisan of the phlogiston theory, he concluded that light
acted here similarly to phlogiston; how this happened could not as
yet be stated definitely, but it was proved by many chemical experi-
ments that light contained phlogiston, or as we say today, acted as
a reducing agent.

Joseph Priestley was a remarkably versatile man. As a youth he
mastered several ancient and modern languages and studied philosophy
and theology. From 1755 his activities were divided in the work of a

IOO

FROM PRIESTLEY TO SENEBIER

dissenting preacher, the writing of liberal theological tracts, and scien-
tific studies. In 1761 he taught languages and belles-lettres at Warring-
ton. About this time he visited London and met Franklin, who lent
him books which enabled him to publish his History and Present State
of Electricity (1767). In the same year he took charge of a chapel
at Millhill, near Leeds, where the proximity of a brewery turned his
mind to the study of the chemistry of gases, and this branch of
chemistry is indebted to no other scientist in a greater degree than to
Priestley, for it was through him that this science assumed a new form.
In 1772 he published his History and Present State of Discoveries
Relating to Vision, Light and Colours, and in 1773 he was appointed
librarian to Lord Shelburne, with him he traveled in Holland, Ger-
many, and France, meeting Lavoisier at Paris, to whom he commun-
icated his experiments with “dephlogisticated air,” now called oxygen
(1774). He also discovered hydrogen chloride, ammonia, sulphurous
acid, nitrogen oxide, and so forth.

His works on chemistry contributed greatly to the construction of
the system of chemistry by the great French chemist Lavoisier. He
also wrote many theological tracts, which brought him into conflict
with the “fundamentalists” of his day, for he inclined to the material-
istic side of spiritual life and, as he said, “generally embraced the
heterodox side of every question.” He also antagonized through these
writings his protector, Lord Shelburne, who parted (1780) from him
as friend after they had lived together for seven years and granted him
a yearly pension of £150. Priestley moved to Birmingham in 1780,
where he became acquainted with Boulton, Watt, Dr. Darwin, and
Josiah Wedgwood, the potter, who assisted him in his experiments by
financial contributions. Here he again turned to the ministry, but
he became involved in severe theological disputes. His sympathies
with the French Revolution caused him to be attacked by a mob in
1791; his house, library, manuscripts, and apparatus were all consumed
in flames, and he scarcely saved his life. With his family he left Eng-
land in 1794 for America, where he bought a farm at Northumberland,
Pa., and resumed his studies. He died there on February 6, 1804.

Opoix, a Frenchman, supplemented in 1777 the earlier statements
of Dufay (1737) as well as those of Bonzius (1757) and demonstrated
that the colors of materials, ribbons, and so forth, do not become
bleached by the simple effect of the air, but that light is the cause; 2 he
adds “because it loses the combustible” element “phlogiston,” that is,
it oxidizes.

FROM PRIESTLEY TO SENEBIER

IOI

The opinion that light contained a complex, combustible “some-
thing” aroused doubt as early as 1 7 8 2 in the mind of Selle, 3 but no better
explanation of the chemical action of light could be found to replace
this view. Even Lavoisier, who was well aware of the importance of
the role which light played in nature and praised it in extravagant
terms, 4 had only highly imperfect conceptions of it. He believed in
a material luminous matter, which combined with some plant particles
and thus formed the color of the plant. Guided by Berthollet’s experi-
ments with chloride of silver, he expressed the opinion “that the matter
of which light is made up has a great affinity for the acid-forming
substance, so that the first combines with the latter, and by the addi-
tion of matter of which heat is composed can be changed into a gaseous
state.” 5

A peculiar statement is made by Gottling, in Taschenbuch fur
Scheidekiinstler und Apotbeker auf das Jahr 1781 (p. 1 89) : “It is said
that the observation has been made that silk, hair, cotton, and the like,
in manner similar to the green leaves of plants under a bell glass in
water when exposed to the sun, will give off living air (oxygen) ( ! ? ) .”

The proper preparation of Bestuscheff’s tincture for the nerves and
of the golden drops of De la Motte from iron chloride and alcohol was
made known to large circles by Professor Murray, at Gottingen, in
an extract from a letter dated at St. Petersburg, April 19, 1780. 6 This
gave the impetus to further modifications in the preparation of this

Martin Heinrich Klaproth changed, in 1782, the prescription for
Bestuscheff’s tincture of iron, using ether instead of alcohol, which
yellow solution he also “blended in light”; he obtained by this method
a strongertincture than with alcohol. He also observed that the solution
of iron chloride in ether lost color more quickly in light than did the
alcohol solution. 7 He offered the explanation for the action of light,
“that this tincture really decomposes the rays of the sun, separates
the phlogiston from it, and combines with it.”

An anonymous writer remarked 3 that iron chloride, even when
not sublimated, will produce a yellow, though turbid, etherized tinc-
ture which will not change color in the sun ( ? ) .

Wenzel, who was one of the most reputable chemists of the
eighteenth century, published in 1782 Lehre von der V erwandtscbaft
der Korper, in which there are many prescriptions for solutions; for
instance, on page 436 he states that nitrate of silver is soluble in spirits

io2 FROM PRIESTLEY TO SENEBIER

of wine in the proportion i oo: 240, which is of interest for the later
photography with collodion.

In 1782 A. Hagemann published his Zufdllige Bemerkung, die blaue
Farbe des Guajacgummis betreffend. 0 He contributes the observation
that if this gum, pulverized, was placed in a glass vessel near a window
it turned blue after a few weeks on the outer surface which faced the
window and was exposed to the light, while the part facing the wall
and the “inside” powder retained its natural color. When some of the
powder was spread on paper and was exposed, it soon changed its
color and became muddy, ash gray, with a slight greenish hue, but
not blue. In a vacuum, however— for instance, in a barometer tube— it
took on a blue color, which was much more beautiful in the shade than
in the sun. “What could be more natural than to fall back on hornsilver
for the explanation of this phenomenon?” asks Hagemann, and ex-
plains the phenomenon by following Scheele’s theory. He states that
gum-guaiacum extracts the phlogiston from the light and then turns
blue, but that it loses the blue color when exposed to air, “durch die
Feuerluft” (through the fiery air), since “das Brennbare wieder
entzogen werde” (the combustible parts will be again withdrawn-
oxidation).

This statement of Hagemann is of considerable historical importance,
when we consider that Niepce at the beginning of his experiments,
according to his own admission, used guaiacum. At any rate it is certain
that the sensitiveness to light of resinous substances dates from Hage-
mann. Senebier admits this priority, and undoubtedly was stimulated
by it to further studies of resins. Directly or indirectly Niepce also
used the same source and arrived at the epoch-making photographic
asphalt process.

The experiments of Jean Senebier, published in 1 7 8 2 , 10 were received
with justified appreciation, owing to their rare thoroughness and great
importance in the development of photochemistry, as well as their
value in plant physiology. J. Senebier (1742-1809) studied theology
and was pastor of a church at Geneva, which post he resigned in 1773
and became chief librarian of Geneva. At first he wrote stories, but
with little success; later he published, in a prize competition given by
the Academy at Haarlem, his classical work Essai sur Fart d' observer
et de faire des experiences (2 vols., Geneva, 1775). He also contributed
an article on plant physiology to the Ency elope die metbodique. His
most important contributions dealt with the application of the laws

FROM PRIESTLEY TO SENEBIER

103

of chemistry and physics to animal and plant life. He paid particular
attention to the action of sunlight. We owe to him the data on the
color change of the different woods in light, which turn darker in it,
such as pine, linden, rosewood, oak, barberry, brazilwood, and so
forth. He described the continued darkening of lignum vitae in light,
as it turned blue in diffused light, grayish green in sunlight; but in this
Senebier conceded the priority of discovery to Hagemann . 11 Also we
are indebted to Senebier for the first knowledge of the changes effected
by light in many other resins. Some fade, as mastic, sandarac, gummi
animae (gum of hymenaea Courbail) , incense. Others become darker,
as gamboge, gum ammoniac , 12 guaiacum. It is quite possible that Niepce
was guided by these statements, together with the earlier ones of
Hagemann, and that the discovery of the light sensitivity of asphalt
may have some direct connection with the knowledge of the facts
established by Senebier. Unfortunately the recognition of this honor
has not been accorded to Senebier or to Hagemann.

Senebier verified the fact that the alcoholic extract from green
vegetable matter (chlorophyll) will fade in only half-filled bottles in
sunlight within twenty minutes; while in completely filled and her-
metically closed bottles, the tincture withstood the action of strongest
sunlight perfectly throughout four months. The green liquid with
nitrogen showed the same behavior when exposed to light. He dis-
covered also that alcoholic tinctures of blossoms of jonquils, roses,
buttercups, saffron became more or less bleached in sunlight; this
also happened with solutions of dragon’s blood, cochineal, fustic, henna
root, safflower, kermes, gum-lac, and so forth. The red alcoholic solu-
tion of dragon’s blood lost its color entirely, the alcoholic solutions of
henna root, safflower, kermes, cochineal changed the red to yellow.
The aqueous solution in water of henna, kermes, and cochineal in con-
trast with the alcoholic ones suffered no change in sunlight. The blos-
soms of the damask rose gave alcohol a brick red color; this tincture
changed first to violet in the light, then the color was entirely destroyed;
a few drops of acid stopped the decomposition of the color in the sun.
Rose blossoms which had turned white, when extracted in alcohol,
regained their color when they were spread out in a dark airy place,
and the process was accelerated by light. This regeneration of the color
did not occur over mercury in an atmosphere of nitrogen, not even
in sunlight. This same behavior was observed in the red skin of plums
and peaches.

FROM PRIESTLEY TO SENEBIER

104

The necessity for the action of light in these color changes was
proved, especially in the case of the tinctures of blossoms, by the fact
that they did not fade when the heat of a stove was substituted for
sunlight. Even at 6o°C. the leaf green did not fade when light was
excluded.

Senebier saw that oils became viscous in light, and at the same time
were bleached, that yellow ivory, yellow silk, and wax faded in the
sun. He also discussed the changes of artists’ colors and mentioned that
cinnabar under water turns muddy in the sun in a short time. 13 He adds
that artists’ water colors withstand the action of sun’s rays far better
when covered with isinglass and then varnished than when varnished
without isinglass.

White nitrous ether, according to Senebier, turns yellow in light
and becomes still more volatile, forming nitrous acid. He is very ex-
plicit about the changes of chloride of silver in light. 14 Hornsilver
sealed in a transparent glass started to turn violet after a few seconds;
after a minute this color became intensified, but it did not penetrate
deeply into the mass of the silver; after an hour had passed, the color
changed to umber and no further change could be noticed. Sunlight
alone produced this result, for the silver remained absolutely white
when sunlight was completely excluded— and the silver was then ex-
posed to heat and cold, to moisture or to very dry air— yes, and even
when placed in a Toricellian tube. When placed in a dimly lighted
room, however, where one could hardly see to read, the silver began
to darken only after eight or ten days. When light was concentrated
on it through a convex lens the silver colored instantaneously. When
from one to three pieces of thin paper were laid on top of the silver
and the sun was allowed to shine on them, the silver changed color in
a few minutes; under four sheets it darkened no longer. In these ex-
periments one may discern the beginning of the paper scale photo-
meter (1782).

A piece of walnut half a line thick (a line =1/12 inch) prevented
the silver which it covered from changing, but a piece of pine of
the same thickness permitted the coloring, undoubtedly on account
of its larger pores, when compared with walnut. Twelve panes of
glass, three-quarters of a line thick, only retarded the coloring with-
out preventing it. Even two inches of water between two pieces of
glass did not keep the silver from turning violet after three minutes.

In regard to the action of the solar spectrum Senebier found, mak-

FROM PRIESTLEY TO SENEBIER

io 5

ing his experiments in a darkened room, that the change of color in
silver took place as follows:

Under violet light

Within 15 seconds

“ purple-colored light

“ 25 “

“ blue light

“ 29 “

“ green light

“ 37 “

“ yellow light

“ 5 Zi minutes

“ orange-colored light

“ 12

“ red light

“ 20

The three last-mentioned lights never

produced as intensive a color

as violet. Senebier also noted that while the colors produced by the
prism imparted a violet color to the silver, it had more of a shade of
violet in it and that this color became lighter in the proportion in which
the rays are refrangible (toward red). This statement gave the first
indication that silver chloride assumes various colors in the spectrum,
and Senebier thus appears as the earliest forerunner of Seebeck’s dis-
covery that the spectrum reproduced itself on chloride of silver in its
own natural colors. He also noted that light projected through red
and violet-colored fluids lost a great deal of its effect on chloride of
silver. These phenomena Senebier explained by stating that light acted
like the “Brennbare” (combustible) , namely, analogous to “the fumes
of liver of sulphur and of coal.” In other words, he considered the
chemical action of light as a reduction.

The serious study on the chemical action of light in the eighteenth
century reached its climax with Senebier; his works contain many
valuable original observations which have kept their full importance
up to this day, but which, for the most part, were not followed up
later, so that Senebier’s works must be considered as a rich source
of knowledge, a veritable treasure trove of little-known facts.

What had happened to the earlier studies of Schulze, Hellot, and
others? About the end of the last century these subjects were bandied
about, here and there, among the most remote branches of literature,
but from the sphere of chemistry and physics they had entirely disap-
peared. On the other hand, magic and legerdemain had appropriated
these phenomena, and along these lines I propose to give a few ex-
amples.

Wiegleb prescribes in his Natiirliches Zauberlexikon (3d ed., 1784,
p. 458), that one should proceed to the manufacture of “sympa-

106 FROM PRIESTLEY TO SENEBIER

thetischer Tinte von Silber” (sympathetic silver ink) in the following
manner:

In a small quantity of aqua fords as much silver is dissolved as possible;
then this solution is mixed with from 2 to 3 times its volume of distilled
water. The characters written with this ink on paper remain invisible
after they are dry, but when the paper is placed in sunlight they will
appear soon after an hour in a blackish color.

The method “to blacken the face” cited on page 42 of Wiegleb’s work
is worthy of note owing to its originality: “The face is moistened with
aqua fords in which fine silver is dissolved, after the solution has
previously been diluted with at least 1 00 times the quantity of water;
then the sun is allowed to shine upon the face, thus one becomes for
some time a black man.” “To imitate ebony” one wets the wood with
a silver solution, allows it to dry by placing it in the open air, making
sure of sunlight, and polishes it with wax.

Who would not recognize immediately in this description the
previous statements of Glauber, in 1658, and of Hellot, in 1727? Joh.
Sam. Halle, in his Magie; oder, Die Zauberkrafte der Natur (1784,
I, 148), recommends using “the magic forces of the sun to produce
black writing inside a glass of water” as especially suited for amuse-
ment; one finds almost verbal reprint of Schulze’s discovery, of course,
without mention of the author.

This same experiment was described also in Poppe’s Neuer Wun-
der-Schauplatz, (1839, I, 323), under the caption “How One Can
Make Writing Appear by a Peculiar Method in a Fluid, Which Is
Contained in a Glass.”

Hellot’s sympathetic ink, which becomes visible in light, has been
described in similar books innumerable times. Among others Accum
found as a welcome contribution to his Chemische Unterhaltungen
(1819, p. 9) the coloring of ivory in the sun by a silver solution. He
also recommends as a source of amusement the experiment, mentioned
later, of the reducing gold by discoloring it in the sun through carbon.
The original experiment is to be attributed to Rumford (1798).

I shall have to content myself with these examples, despite the
temptation to pursue our investigations into the farthest corners of
literature in the most extensive manner, in order to follow step by
step the gradual development of photochemistry from so many angles.

Notwithstanding all these bypaths coming from and going toward

FROM SCOPOLI TO RUMFORD

107

all directions, the road of the history of the development of photo-
graphy led directly from Schulze (1727) via Scheele (1777) and his
followers, and particularly in England through Dr. Lewis, in a
straight line toward Wedgwood and Davy, and from them to Talbot
in the thirties of the nineteenth century.

Chapter XIV. from scopoli (i 7 8 3 ) to rum-
ford (1798)

It was in 1783 that the mining engineer Giovanni Antonio Scopoli, 1
of the University of Pavia, made, as far as I can ascertain, the first
observations of the change of potassium ferrocyanide in light. 2 He
mixed a solution of ferrocyanide with some acetic acid and exposed
it to light: “the fluid soon turned green, and after fifteen minutes some
Prussian blue separated.” When the experiment was continued a part
of the Prussian blue settled firmly on the glass, “where it was touched
by the sun.” In the dark there was no precipitation at 37-66°C. Scopoli
concludes that “the effect of the entity which is light upon the color-
ing matter of substances is readily seen, and no doubt it represents one
of their constituents.”

THE PHOTOCHEMICAL EXPERIMENTS OF BERTHOLLET; DISCOVERY OF
THE REACTION TO LIGHT OF CHLORINE WATER ( I 78 5)

Science owes the discovery that chlorine water is light sensitive
(decomposition of water under liberation of oxygen) to Comte Claude
Louis Berthollet, (1748-1822). He studied in Turin and Paris, where
he was elected a member of the Academy of Sciences in 1780. He
followed Bonaparte to Egypt and had at one time the commission
to select the works of art which were to be removed to France. On
his return to France, Napoleon made him a count and grand officer
of the Legion of Honor. He was especially active in organizing
French scholastic education.

One of the most distinguished theoretical chemists of his time, he
discovered the constituents of ammonia and experimented with chlo-
rine and fulminate of silver.

Berthollet made an important discovery in 1785 in the field of photo-
chemistry. He noted that from chlorine water which was standing
in the light little bubbles arose, which he identified as “vital air”

io8 FROM SCOPOLI TO RUMFORD

(oxygen). In the dark he could not effect this decomposition, not
even at ioo°C. 3 This discovery led Saussure, eleven years later, to
the construction of the first chemical photometer.

In his dissertation De /’ influence de la lumiere (1785) Berthollet
states this: “All these effects of light, that is, on vegetation, on nitric
acid and on hornsilver, were attributed to phlogiston; but with later
advances in chemistry this hypothesis was found insufficient and un-
necessary.” In order to make sure of just what the action of light
consisted, he tried several experiments:

I have exposed to light a bottle, totally filled with chlorine water (deph-
logistonated hydrochloric acid), the neck of which bottle was connected
by a tube with a pneumatic apparatus; soon after I noticed a great number
of small bubbles being liberated from the liquid everywhere, and after
several days I found on the tube which was connected in the apparatus,
a certain quantity of gas, which was nothing but “vital air.” As the air
was disengaged from the acid, it lost also its yellow color, so that finally
it appeared completely like pure water.

In this state it did not bleach the blue vegetable colors (litmus) but
only turned them red, and in general retained very little of its odor;
it effervesced with alkalis, in short, the chlorine water (dephlogis-
tonated hydrochloric acid) was now nothing more than muriatic
acid (hydrogen chloride). By this experiment Berthollet also en-
deavored to determine how much muriatic acid and oxygen were
formed. When a bottle was filled with the same liquid and was
covered with black paper, it underwent no change and “no air was
developed.” At ioo°C., it is true, chlorine gas escaped, but this was
entirely absorbed in cold water and gave off “no air”; the residue
remaining in the retort did not show the property of effervescing with
fixed alkali (potash, etc.). In another distillation bulbs containing
chlorine water, when heated directly above glowing coals, formed
also a little oxygen in addition to chlorine gas and a residue, which
effervesced with alkaline carbonate (showing presence of muriatic
acid).

“This experiment proves definitely,” concluded Berthollet, “that
light not only acts entirely differently from heat but also possesses
the quality of ‘vital air’ which exists in the combined state, namely,
to give elasticity (to liberate combined oxygen as gas), and it is this
which gives it its excellent action.”

This Berthollet confirmed by his experiments with nitric acid, from

FROM SCOPOLI TO RUMFORD

109

which after a few days, when exposed to sunlight, a considerable
amount of oxygen developed, while under heat, he thought, only
nitrous gas escaped.

In 1786 Scheele supplemented his former statement, as well as that
of Priestley, on the decomposition of nitric acid in light. 4 He noticed
the development of oxygen, which fact had hitherto escaped his notice.
For when he lifted the stopper from a bottle which was not quite
filled and had been standing in the sun, a gas blew out violently, and
he identified it as oxygen. The date of this experiment was 178 6, the
year of Scheele’s death.

Berthollet 4 repeated this experiment in the same year and reached
the same result; he also found that phosphorus “turns red in light and
is oxidized by chlorine water.”

Of great interest is his observation that silver chloride, exposed to
light under water, formed gas bubbles “to all appearances vital air.”
Thus he recognized the fundamental photochemical reaction of the
blackening of silver chloride. But the silver is said to be not reduced
to its metallic state, “but still retains some vital air.” 5

The particular passage reads: “When hornsilver over which water
has been poured is exposed to light, the surface will quickly turn
black and a number of small bubbles will escape from the bottom,
which are to all intents vital air . . . for these are not bound tight to
the silver chalk. The silver chalk has meanwhile not returned to its
metallic state; it still retains some vital air . . . because the complete
reduction of the metal oxides to metal was always difficult to attain.”

According to these statements Berthollet was the first who expressed
the opinion that on exposure to light chloride of silver changes, not
into metallic silver, but into argentous chloride or argentic oxy-
chloride, which view often turns up in later years.

From these experiments he concluded not only that light acted
entirely differently from heat, but that it possessed also the property
to impart elasticity to “vital air” (when in a combined state) and that
this represents its chief effect (i.e., that it liberates oxygen from its
combinations and changes it to a gaseous state). The theories of phlo-
giston he declared inadequate and antiquated. However, he later modi-
fied his views on this subject considerably. 8

Bindheim informs us (1787) that a silver solution filtered through
gray paper precipitates metallic silver faster than ordinarily. 7

Robison sought to discover by experiments whether nitric acid be-

I 10

FROM SCOPOLI TO RUMFORD

came fuming (i.e., yellow and vaporous) through the same “elementary
matter of light” which blackened silver salts. He caused sunlight to
fall on a glass filled with colorless nitric acid and then on nitrate of
silver (-paper?), presuming that the sunlight would have no effect
at all on the silver salt, or at least a weaker effect, since it had already
produced one of these effects. He found, indeed, a considerable de-
crease in the action of light due to the interposition of the nitric acid.
Unfortunately, Robison had to interrupt his experiments in 1787,
owing to his shattered health. 8

It cannot be denied that Robison already had a clear conception of
the idea which later caused Draper, among others, to lay down the
principle that when light is employed in the chemical process, some
of its rays are absorbed and this part is robbed partially or entirely of
its capability to produce any further chemical effects.

In 1788 Chaptal 9 investigated the salt “vegetations” and stated that
the metallic salts (sulphate of iron, sulphate of zinc) promote vegeta-
tion especially well on the side turned to light. Chaptal stated: 10
It is really an astonishing manifestation to a chemist when he sees the
various dissolved saline substances creep up the sides of the vessel and,
having reached the top, throw themselves over the sides. This phenomenon,
which differs widely from crystallization and does not operate in the
liquid state, becomes visible only after the salts have formed and have
lost the water of crystallization, which phenomenon I call saline vegetation.

This caught his attention and excited his desire to make his own
investigations of the subject. For this purpose he took several glass
bowls and half covered the upper and lower parts with black taffeta.
These vessels he filled with salt solutions and placed on a table in a
completely darkened room, except for the light coming through a
small hole in the curtain. The vessels were arranged so that only the
uncovered parts could catch the light, while the covered portions were
in almost total darkness. Air currents were carefully excluded, for
he selected both the rooms and their chimneys for the installation of
his apparatus with care and filled up all cracks in doors and windows.
Chaptal made more than two hundred tests and verified that the
vegetation appeared nowhere but on the side exposed to light. This
result was so apparent that in nearly all solutions the salts vegetated
in a few days, often in twenty-four hours, some distance above the
surface of the fluid, but only on the lighted side, while on the dark
side, not even the smallest trace of any kind of a crust or anything

FROM SCOPOLI TO RUMFORD

1 1 1

similar showed. Iron sulphate and zinc sulphate kept strictly within
such boundary lines and showed usually the strongest vegetation in
those parts which were most intensely illuminated. Along these lines
many species of salts were examined. (Metallic salts, alkaline earth
salts, and alkaline salts; iron, copper and zinc sulphates, soda, potassium
sulphate, alum, acetate of lime, saltpeter, seasalt, tin salt, etc.) The form
which each of these salts assumed during this vegetation offered very
curious differences; sometimes crusts or small leaves and in other in-
stances needles, which formed nets and meshes, or which united in
concentric form or formed tassels, etc.

That light alone does not create these results, that air must be added,
and that evaporation must be made possible is a matter of course, but
all this Chaptal carefully demonstrated in his experiments.

Finally, Chaptal proposed these questions: “Is it, perhaps, a kind of
affinity among air, light, and the saline substances which lifts the
latter and enables them to overcome the force of gravity? Is this a
kind of real vital energy, which is aroused and ferments by the admis-
sion of air and light?” But Chaptal did not risk an answer to these
questions.

Dize, on the contrary, saw no influence of light on the salt vegeta-
tions when examined in a vacuum. 11 He published several criticisms
on Chaptal’s dissertation in February, 1789, mostly of a historical
nature. He called attention to the younger Lemery, who presented
to the academy in 1 707 observations on salt vegetation, and also to two
dissertations dealing with the same subject published by Petit, in 1722.
Petit arrived at the same conclusions as Chaptal, namely, that air and
light were indispensable to this operation, and he found that these
kinds of vegetations were not different from those that took place
by an imperceptible evaporation of liquids. Dize states that this
vegetation takes place just as well in the dark. But these experiments
in no wise contradict the fact that this vegetation of the salts proceeds
faster and better in those parts exposed to light than in the dark.

Priestley, in 1789, referred once more to the decomposition of nitric
acid. 12 He found that nitric acid became colored in heat without light
and made further studies concerning this, which are of no interest here.

Dorthes found, in 1790, that the vapors of water, alcohol, ether,
and especially of camphor will settle on the side of a glass vessel
most abundantly where the vessel is struck by light. 13

i iz FROM SCOPOLI TO RUMFORD

INVENTION OF THE FIRST CHEMICAL PHOTOMETER BY SAUSSURE,

IN 179O, AND HIS OTHER DISCOVERIES

Berthollet’s statements on the behavior of chlorine water in light
urged Saussure to construct the first chemical photometer. 14 Horace
Benedict de Saussure (1740-1799), Swiss physicist, interested him-
self early in the natural sciences and was appointed professor of
philosophy in Geneva when he was only twenty-two years old. He
explored particularly the Alps, acquired the highest merit in geology
and geophysics, invented the hair-hygrometer (1783), and made
barometric measurements, particularly among the Alpine summits.
Senebier wrote his biography, Memoires historiques sur la vie et les
ecrits de H. S. de Saussure (1801), and continued to some extent his
works. In commemoration of his services in the exploration of the
Alps, a monument to Saussure was erected at Chamonix, Mont Blanc,
France. He was the second who made the ascent of this “Monarch of
the Alps.”

Saussure experimented with measurements of the sun’s rays at
high altitudes, using chlorine water, which liberates oxygen gas in
light; this was discovered by Berthollet in 1785. Saussure noticed that
the ratio of development of the quantity of gas was proportional to
the intensity of light and proposed the construction of a photometer
based on this reaction. The decomposition of chlorine water took place
much faster, on account of the greater intensity of the light, on Mont
Blanc than in the valley. Wittwer, as is well known, revived later
(1855) the use of chlorine water for photometry, but the priority of
the idea belongs to Saussure, a fact to which the author of this history
was the first to call attention. 15 Saussure, who deserves the title of
father of chemical light measurement, also investigated the action of
light on colored materials, which he made on the Geant and at
Chamonix (1788). He chose, on the advice of Senebier, the materials
enumerated below. They were exposed to the sun from 1 1 o’clock to
2 o’clock. The fact is, differences were conspicuous, which Saussure
noted in figures, guided by the principles of the construction of his
cyanometer and diaphanometer.

Saussure’s “cyanometer” is a device for determining the intensity of
the blue color of the clear sky. Saussure painted fifty-three strips of
paper in colors ranging from white to pure Prussian blue. To a series
of such mixtures from the palest to the most intense blue, he added also
black, in order to make the blue still darker. With these colored strips

FROM SCOPOLI TO RUMFORD

113

he compared the blue of the sky under various meteorological con-
ditions. This is historically interesting, for Professor Ostwald, in his
modern color theory, establishes a system of color tabulations in his
Farbenatlas which also starts from pure hues; to these are added vari-
able proportions of white and black. Thus it seems justifiable to con-
sider Saussure in this respect the predecessor of Ostwald.

The “diaphanometer” of Saussure is a device for acertaining the
transparency of air, that is, the diminution of the intensity of light
as effected by the air. On a disk 2 m. ( 6]/ 2 ft.) in diameter there is
drawn a black circle 60 cm. (23 f 2 in.) in diameter. On a second circle
20 cm. (8 in.) in diameter there is a black circle 6 cm. ( z / 2 in.) in
diameter. Supposing the two disks are illuminated equally and that the
air does not absorb any light, then the distances at which the circles
vanish from the eye of the observer must be proportional to the dia-
meters of the circles. The larger circle becomes invisible earlier if at
a greater distance the contrast between the black disk and the white
disk becomes less, due to absorption of light.

VARIATION OF BLEACHING EFFECT

Pale rose-red silk ribbon
Deep rose-red silk ribbon
Violet silk ribbon
Blue silk ribbon
Green silk ribbon
Green paper
Sky-blue paper
Barberry wood

Average figures

At Chamonix On the Geant

2.45

2 -73

6.43

8.86

0.61

2.05

1. 16

. . .

0.93

. . .

1.43

7.68

0.61

5.46

9.1 1

2.83

5-*7

All colors faded; only barberry wood and green paper turned brown.
Again, on the mountain the action of light was decidely more ener-
getic than on the lower levels. That the color change in all examples,
under the same conditions, was not alike (for instance, green paper
5-6 times more; blue, on the contary, the same in both cases) Saus-
sure believed could be traced to the fact that the moisture content of
certain colors played a greater role in some than in others.

Senebier now devoted himself again to photochemical experiments
and investigated 18 the role which air plays in the change noted in oils
when exposed to light. On April 26, 1790, he placed pure olive oil
so that light could act on it in part by excluding air and in part by

FROM SCOPOLI TO RUMFORD

1 14

admitting it. The oil soon turned brown, then white again, and became
very rancid and viscous after about a month; later it underwent no
further change. When air was shut out, hardly any change was evident
after almost a month; then a green substance formed; still later a
distinct change took place. He concluded: “Light favors the com-
bination of oxygen with oil, because it thickens faster when light and
air are both admitted than in air alone in a dark place. It seems that
light alone will not cause oil to become rancid, so long as air does not
touch it.” He also remarks: “I noticed that fat oils, those that easily
freeze, especially sweet oil, which freezes at 7°-8°R, did not freeze at
50°R after it had been exposed to the action of air and light during
the summer; in this detail it resembled the dry oils, which freeze very
slowly.”

In 1791 Berthollet published his important work on dyeing and
bleaching under the title Elements de Part de la teinture (Paris) . 17 It
is there demonstrated, with respect to the bleaching process with
chlorine, that in the bleaching-out of organic coloring matter oxygen
plays a great role, since it combines with the particles of the coloring
matter and, so to speak, burns and bleaches them. 18 Berthollet also
continued Senebier’s experiments and tried to ascertain whether
oxygen is absorbed or not during the decomposition of the coloring
matter in light. He half filled a bottle with an alcoholic solution of
chlorophyll and placed it upside down in mercury. When he exposed
it to sunlight, the color became decomposed and at the same time the
mercury rose in the bottle. This showed that “the oxygen had been
absorbed and combined with the color particles.” He continues:

When there is no oxygen in the glass which contains the fluid, then the
light shows no effect upon the coloring matter, the nitrogen suffers no
diminution ... I placed tincture of litmus in contact, both in the dark
and in the light, over mercury with oxygen gas; the first remained un-
changed for a long time and did not reduce the quality of gas; the second,
however, lost a great deal of its color, turned red and the oxygen was
largely absorbed. He believed that some carbonic acid formed, which no
doubt caused the change from blue to red.

Therefore Berthollet concludes that it is demonstrated “that light
promoted the absorption of oxygen through coloring matter.”

FURTHER ADVANCES IN PHOTOCHEMISTRY UP TO 1 798

The knowledge of light-sensitive mercury salts was greatly enlarged

FROM SCOPOLI TO RUMFORD

1 >5

in 1786 through Hahnemann’s discovery of “soluble mercury” (Mer-
curius solubilis Hahnemanni). In order to retain its black color, it
is necessary to dry the black precipitate in darkness, this precipitate
being formed by mixing nitric acid and mercurous oxide solution with
ammonia. While Hahnemann saw that his preparation was partly re-
duced in the sun to a metallic state, he did not know that this does not
happen in the dark. Therefore, it seems that he was not really aware
of the light-sensitivity of this combination. 19

Further details concerning the chemical decomposition of mercury
salts are pointed out by A. F. de Fourcroy, in 1791. 20 He found that
the gray precipitate formed by dissolving sulphuric mercurous oxide
in a small quantity of ammonia was in sunlight reduced partly to metal,
while another part changed into a dark powder, soluble in ammonia
and capable of further reduction. When much ammonia was used,
however, in the precipitation of the mercury salts, Fourcroy states,
a darker precipitate formed which could be reduced completely in
the light. 21

In 1792 Vasalli presented to the Royal Academy of Sciences of
Turin his investigations on silver chloride. 22 First, he determined quite
definitely that not only sunlight but also light from candles and lamps
has a chemical property, namely, the ability to effect a change of color
in silver chloride, even though very slightly. 23 He stated, in a supple-
mental note, that moonlight concentrated through a convex lens also
colored silver chloride within four hours and that for the process of
bleaching wax water was not needed. 24 He further stated that potas-
sium nitrate or sodium chloride crystals always crystallize on the side
exposed to light.

In the Journal fur Fabrik, Manufaktur und Handlung (August,
1792, p. 65) can be found a contribution by an unknown author,
entitled “Versuch einer kurzen Einleitung in die Farbenlehre und
Farberei.” In this there are several mentions of the remarkable effect
of light on different substances, and among others that it was “well
known” that wool, when dyed in a woad vat or in an indigo vat,
looked green at first, but when it was struck by light, turned dark
blue. Also:

The leaves from two species of varnish or lacquer trees (toxicodendron
triphyllum. Folio sinuato rubescente and T. triphyllum glabrum) contain
a milky sap. which, when exposed to light, turns a beautiful black; it colors
the canvass without attacking and corroding it and also resists the action

1 16 FROM SCOPOLI TO RUMFORD

of alkali .... Orseille acquires, in a solution of stannous chloride, a more
permanent color proportionally as the solution changes into scarlet ....
The orange color of Orleans (bixin) or Rocou (annato) and the beautiful
yellow of Avignon berries and Curcuma fade very rapidly under the
influence of light.

J. R. Trommsdorff declared, in 1793, 25 that benzoate of silver “re-
mains unchanged in the air, but turns brown in sunlight.”

Interesting is the opinion published by Buonvicino, in 1793, that
basic mercuric sulphate turns black in light and is even said to increase
in weight when enclosed in a hermetically sealed tube. 26 The phlogis-
ton theory may have led him astray in his belief as to this increase
(phlogiston absorption?). Trommsdorff, who seems to have had no
knowledge of these statements, stated also, in 1796, that the yellow
precipitate “which forms when one precipitates a solution of mercury
in nitric acid with sodium sulphate” (that is, turbith) will turn a “dirty
greenish gray” on the surface in the light; he does not mention an in-
crease in weight. It was not until 1799 that Humboldt contradicted
this statement of Buonvicino relative to the increase of weight and
found that mercuric sulphate does not become heavier under light. 27

Gottling, in 1794, advanced the strange opinion that oxygen by
sunlight was not only degenerated, but that it was almost completely
changed into nitrogen. 28 He forgot that in such a case our whole atmos-
phere would have been transformed long ago into nitrogen. Gren, 29
and later Bockmann, 30 contradicted this false statement and disproved
it completely.

The property of metals to precipitate when in the state of solution
by reducible substances gave an English woman, Mrs. Fulhame, the
idea of employing this in the manufacture of gilt and silver cloths,
inciting her to a series of interesting experiments on this subject. After
the activity, although disputed, of Princess Eudoxia, we see for the
second time within several centuries a woman interesting herself in
the development of photochemistry.

In her meritorious work An Essay on Combustion; with a View
to a New Art of Dying and Fainting, wherein the Phlogistic and Anti-
phlogistic Hypotheses Are Proved Erroneous (1794), Mrs. Fulhame
describes, 31 along with a number of other experiments, the different
media to be used in order to reduce metals by the wet process and how
the salts contained in silk material after having been soaked in a solution
of chloride of gold or nitrate of silver are reduced to metal in light.

FROM SCOPOLI TO RUMFORD

1 17

In the eighth chapter she deals with the reduction of metals by light.
First, she points out that water alone cannot effect the reduction of
the gold or silver solution and that light alone, in the absence of water,
reduces the gold and silver salts; on the other hand, water and light
together inevitably produce this effect. In this experiment a piece of
silk material was dipped in a solution of chloride of gold or nitrate
of silver and exposed to sunlight, the material being in the meantime
soaked in water. The material which had been impregnated with the
gold solution soon changed its color to a weak green; then followed
a purple; and finally, after fifteen to sixty minutes, a crust of reduced
gold formed. In the case of the silver solution, the material turned
reddish brown, and finally, after about four hours, grayish black.
But when the experiment was made by wetting the silk with alcohol
instead of water, the reduction which took place was very weak in the
case of silver and none at all in gold, which was ascribed to the moisture
of alcohol and air. In another experiment the silk soaked in silver nitrate
was dried by heat and exposed to sunlight; the stuff turned reddish
brown after less than an hour, and on the third day, black. This effect
as well was attributed to the moisture in the atmosphere.

Mrs. Fulhame drew the following conclusions from her experi-
ments: “That water is absolutely necessary to the reduction of metals
by light . . . that light acts in this reduction just like hydrogen, sul-
phur, and carbon . . . that light could accomplish this only through
the decomposition of water.” Mrs. Fulhame’s statements are original
and important. They led to Rumford’s investigations and were in-
directly responsible for serious attacks on the followers of the theory
of the chemical effects of light.

Meanwhile, the hypothesis had developed that light consists of a
modified heat substance. Girtaner was the first to express this view,
in his Anfangsgriinde der antiphlogistischen Theorien (1795, p. 14),
and Link followed, in his “Beobachtungen and Betrachtungen fiber
den Warmestoff” (II, 7), of his Beitrdge zur Pbysik und Cbemie
(1795). Scherer went even farther and in his Nachtrdge zu den
Grundziigen der neuen chemischenTheorie (Jena, 1796, p. 18) denied
every individual chemical influence of light even on plants; he sought
to trace back all these phenomena to the effect of heat. He declared
erroneous all observations not in harmony with this hypothesis and all
experiments carried on for their substantiation fallacious. 32

Count Rumford also sided with this opinion and tried to support

1 18 FROM SCOPOLI TO RUMFORD

it with his experiments, which, however, were not original, but were
to a great extent those of Mrs. Fulhame.

He writes:

In the second part of my seventh essay, On the Propagation of Heat in
Fluids, I have mentioned the reasons which had induced me to doubt the
existence of those chemical properties in light that have been attributed
to it and to conclude that all these visible changes which are produced in
bodies by exposure to the sun’s rays are effected, not by any chemical
combination of the matter of light with such bodies, but merely by the
heat which is generated or excited by the light that is absorbed by them.

He then details at length a host of experiments he made in silvering
and gilding cloths and other materials, saying that he did this because
Mrs. Fulhame’s experiments suggested it— and finally comes to the
“conclusion” he gave in the first paragraph of his essay as given above.
He does not, however, in any part of the essay refer to the “con-
clusion” given in the first paragraph, but simply details eighteen
experiments and states that they may “induce others to pursue these
interesting investigations.”

Among his experiments, the one of special interest is that which
tells of silvering a piece of ivory in dilute nitrate of silver solution.
This was

suffered to remain in a dark closet till the ivory had acquired a deep or
bright yellow color . . . then immersed in a tumbler of pure water and
immediately exposed in the water to the direct rays of the bright sun.
The instant the sunbeams fell on the ivory it began to change color and in
less than two minutes ... it became quite black.

He refers to this discoloration as a coaly substance (oxidation) which
could be rubbed off, and when the ivory was again put in water and
again exposed to sun the discoloration began again— “the oxide of the
metal penetrating the ivory to a considerable depth.”

Juch repeated, in 1799, Rumford’s experiments with very slight
changes and arrived, as might be expected, at the same conclusions:
the action of light does not differ from heat. 33

However, these mistakes had no injurious effect on the develop-
ment of photochemistry.

Chapter XV. from vauquelin (i 79 8) to

DAVY (1802)

VAUQUELIN DISCOVERS CHROMIUM, THE SENSITIVITY TO LIGHT OF SILVER
CHROMATES, AND THAT OF SILVER CITRATE ( I 798)

In 1798 the celebrated French chemist Louis Nicolas Vauquelin (1763-
1829) discovered chromium during his work on the analyses of min-
erals. Vauquelin was one of the best-known chemists of his time.
First he was a pharmacist at Rouen, and later, in Paris, an inspector of
mines. He became assistant in chemistry at the Ecole Polytechnique,
and professor at the College de France and, after the death of Fourcroy
in 1 808, at the medical faculty in Paris. His labors covered the whole
field of chemistry, but he specialized in the analysis of minerals. It was
while making an analysis of the then newly-found mineral, Siberian
red lead (PbCrC>4), that Vauquelin discovered chromium and inves-
tigated its compound, particularly the chromates. The new metallic
element he called “chrome” after the Greek word chromos— color.
Vauquelin observed that chromic acid forms with silver a carmine
red salt (“un precipite du plus beau rouge de carmin”) which turned
purple (“pourpre”) when exposed to light. 1 Thus he discovered the
light-sensitivity of one of the chromium compounds. But this com-
pound was a silver salt, and therefore this reaction really belonged to
the photochemistry of silver compounds. It was Suckow who found,
in 1 83 2, the light-sensitivity of bichromate of potassium in the presence
of organic salts, that is, by itself without silver salts. He must be
recognized as the first discoverer of this light reaction. The first
application of printing on paper treated with potassium bichromate
was made by Mungo Ponton (1839) after the publication of the
daguerreotype process.

Vauquelin also investigated more exhaustively citric acid, which
was first produced by Scheele, in 1784, and described its salts, among
them the silver salt, concerning which he states that citrate of silver,
exposed to light, takes on “a color similar to black ink.” 2 We must not
overlook the fact that citrate of silver played an important role in the
manufacture of printing-out paper.

FURTHER PROGRESS IN PHOTOCHEMISTRY

Giovanni Valentino Mattia Fabroni (1752-1822) 3 observed in 1798
that aloe leaves contain a juice which in the air— “light may strike it or

I 20

FROM VAUQUELIN TO DAVY

not”— turns gradually to a purple-violet color, which pigment he con-
sidered very permanent. Of other organic colors, scarlet, he found,
belongs to the fast colors, “since it suffers almost no change from the
effects of light or air”; that the safflower (bastard saffron) was erron-
eously included among the fast colors, since it bleached quickly under
the influence of both light and air; and that orseille and the other mosses
rapidly change their violet color to blue in sunlight. 4

In the meantime sufficient empirical observations on the chemical
actions of light were collected so that their conformity to the various
hypotheses of the nature of light could be demonstrated. In the main
the dispute hinged on the point whether light had as basis a particular
matter (Newton’s theory) or was caused only by vibrations of the
ether (Huygens’s theory) . The prevalent view of the time is very well
expressed in Gehlen’s Pbysikalisches Worterbuch (Leipzig, 1798, II,
902):

It seems, however, that a closer acquaintance with chemistry must incline
everyone toward the system of emanation, because most chemists not
only accept a “light substance,” but are accustomed to consider it for their
best theories as an essential ingredient .... In fact there are phenomena
where the light displays an affinity to other substances and creates changes
in the combination and decomposition of matter which are difficult to
ascribe to mere vibrations of the ether.

As proof, he adduces the effect of light on chlorophyll, on silver salts,
on dyestuffs, etc.

This view agrees with that of Kries, the editor and commentator
of Euler’s letters, who had laid down the precise hypothesis some years
earlier, which also declares: “One had observed the action of light
which cannot possibly be explained by simple vibrations and which
makes it more than probable that light in very many of nature’s
processes co-operates as something material.” 5 The proof for this Kries
sought in the photochemical phenomena known at that time.

Davy proposed, in 1799, the idea that light is a particular form of
matter which reacts simultaneously with oxygen to form oxides, that
is, that oxygen gas was a combination of oxygen and light. 0 He himself
later declared this statement to have been too hasty (1802).

The year 1 800 was rich in investigations and experiments in the field
of chemistry. Buchholz observed the blackening of silver carbonate in
light. 7 He found that the blackening of this compound always took
place only on the surface and that even after three months, having
stirred the mixture thrice daily, he did not succeed in blackening the

FROM VAUQUELIN TO DAVY 121

entire material through and through; there was also no loss of weight.

Abildgaard, a physician in Copenhagen (1740-1801), mentioned
as early as December 14, 1797, in a letter to Hermstadt, that half an
ounce of red oxide of mercury, when placed in the Torricellian vacuum
of a glass globe, turned brown or gray after three months. He published
this in 1 800 and demonstrated that red mercury oxide blackens super-
ficially in the sun, that this process occurs even in a vacuum, and that
along with it a gas (oxygen) is liberated, the nature of which, how-
ever, he did not recognize. 8

Bockmann experimented with the influence of light on phosphorus, 9
and observed the formation of a red powdery deposit on the side of
the glass vessel exposed to the sun, in which he usually found ordinary
phosphorus in a nitrogen or hydrogen atmosphere. The precipitation
was accelerated by the simultaneous effect of heat and light, was re-
tarded in the cold, and did not occur when light was excluded. Parrot
applied himself to this subject almost at the same time; he found that
phosphorus in the air, as well as under water, turns yellow in the sun
and that phosphorus in a tincture of blue litmus changed faster than
in a solution of yellow saffron. 10

Girtaner, in a letter to Trommsdorff, 11 opposes the statement that
“light substance” was nothing but an “excited heat substance,” because
on the basis of this belief it could not be explained why chloride of
silver was more rapidly changed by violet rays than by red ones and
why chlorine water yielded more oxygen when exposed to light at
a temperature below the freezing point than in a warm place when
the sky was cloudy.

The first, although not very distinct, mention of the light-sensi-
tivity of molybdic acid I found in 1 800. Daniel Jager described many
experiments with different colors in the Anzeigen der Kurfurstlichen
okonomischen Gesellschaft zu Leipzig, von der Michaelismesse des
Jahres 1 800, 12 and he mentions, among other tests, that he impregnated
a strip of calico with a solution of potassium molybdate, which he then
dipped into a cold solution of a tin salt and found that it “took on a light
blue color of dull and somewhat dirty appearance . . . which in sunlight
and air, instead of fading and becoming duller, gained in intensity.
The green shades usually changed to blue, but after awhile regained
their former appearance completely in the shade and in damp cold air.”

Kasteleyn found that ferriferrous salammoniac sublimate crystals
change color in sunlight and become darker. 13

In the Handbuch fiir Fabrikanten, Kiinstler, Handwerker ... 14 for

122

FROM VAUQUELIN TO DAVY

1800 the remark is found that brazilwood and campeachy wood (log-
wood) lose their strength completely when they are exposed for a
long time to light, air, and the rays of the sun and that they then give
a poor brown color. “If they are to be preserved in good shape, they
must be carefully kept from air, light, and the rays of the sun.”

THE ESSAYS ON LIGHT BY JOHANN CHRISTOF EBERMAIER
AND ERNST HORN, IN 1 797

These very important dissertations, which dealt with the action of
light in nature and particularly with its effect on the human body,
resulted from a prize competition offered by the medical faculty at
Gottingen in 1 796. The question proposed was “What is the efficacy
of light on the living human body, not only the noxious efficacy, but
that useful and salutary efficacy which is over and above that con-
cerned in vision?” According to Professor Placidus Heinrich, Dr.
Johann Edwin Christof Ebermaier received the prize for a disserta-
tion which was published first under the title Commentatio de lucis
in corpus humanum vivum praeter visum efficacia, praemio ornata
(Gottingen, 1797). Later he published a German edition under the
title V er such einer Geschichte des Lichtes in Riicksicht seines Ein-
flusses auf die gesamte Natur und auf den menschlichen Korper, ausser
dem Gesichte, bosonders (Osnabriick, 1799).

Respecting his career, it may be stated that Johann Edwin Christof
Ebermaier was born April 19, 1769, at Melle, near Osnabriick. At first
he followed his father’s profession of pharmacist, then studied medi-
cine at Gottingen. While studying there, he followed the Hanover
troops as surgeon to Brabant and lived for some time in Leyden. He
received his doctor’s degree after his return to Gottingen in 1797. He
settled first in Rheda, later in Osnabriick, was appointed court phy-
sician and councillor at Tecklenburg, and in 1805 became departmen-
tal physician of the Ruhr Department in Dortmund in 1810, govern-
ment and medical councillor at Cleve in 1816, was transferred, in 1821,
to Diisseldorf, where he died on February 21, 1825.

Among several prize essays h e published two dissertations o n medi-
cinal plants; he was also contributing editor to several medical en-
cyclopedias and collected works (see A. Hirsch, Biogr. Lexicon,
II, 259).

Another contribution by Dr. Ernst Horn to the prize competition
in June, 1797, which received the first prize, was one with the motto

FROM VAUQUELIN TO DAVY 123

“In disputation one must seek no authorities but the force of reason,”
which by unanimous decision was deemed worthy of publication. It
was printed in both Latin and German.

Horn was born in Braunschweig, August 24, 1774, and received
his doctor’s degree in 1797 at Gottingen. According to the custom
of those days he traveled extensively, studying in Germany, Switzer-
land, and France. In 1 800 he became professor at the clinic for military
surgery at Braunschweig; in 1804 he received a call as professor in
ordinary for medicine at Wittenberg, and in the same year served at
Erlangen in a like capacity. In 1 806 he became professor at the medical
and surgical military academy and second physician at the Charite
Hospital in Berlin. While holding this position he was forced to de-
fend an exciting criminal process due to a denunciation, from which
he emerged thoroughly vindicated. He died September 27, 1848. His
biography indicates that he acquired special merits in scientific and
applied psychiatry.

Both of these dissertations demonstrate that medical studies at the
end of the eighteenth century did not neglect the consideration of
the biological effects of light and that as early as this a beginning was
made toward a practical light hygiene and light therapy, all, unfor-
tunately, neglected and forgotten. Professor Leopold Freund, Vienna,
first called attention to this in his dissertation V ergessene Pioniere der
Lichttberapie ( Strahlentherapie , 1928 XXX, 595).

The writings o f Ebermaier and Horn epitomize the knowledge and
speculation of that time concerning the action of light on organic
matter and on the human body. It was not customary, nor was it the
intention of the authors, to demonstrate the correctness of the pre-
vailing view by experiments on human bodies or animals or by
eliminating all other elements entering into the results. Both authors,
however, adduced a series of facts which reveal excellent gifts of
observation and acumen; the conclusions which they drew from
their experience, as well as the incitement to a practical light therapy
which they urge, also prove a splendid training in logical thinking.

The question of the nature of light Horn leaves open. It is true that
he mentions both Newton’s theory of emission and Euler’s polemic
against it. The investigations of Young, which strongly supported
the wave theory of Huygens, were evidently unknown to him. Eber-
maier believed that the most satisfying and natural explanation for all
effects of light is the acceptance of and the belief in a peculiar, ex-

12 4 FROM VAUQUELIN TO DAVY

tremely fine, elastic and expansible light substance. Horn did not
consider it proven to his satisfaction that light produces chemical action
on the human body. He could only accept the possibility of such
action as at most a hypothesis, considering the state of the experience
at that time, while Ebermaier had no doubt that the light substance
could enter into chemical combinations with the human body. The
property of light, which, according to De Lucs, possessed in itself no
warmth, to create heat in the body, was explained by both authors by
the assertion that light liberates a heat substance which is combined
in the body— “fire matter,” which is contained in varying degrees in
different bodies. Horn also mentions, however, the theory of Fourcroy
that the rays of the sun create warmth through the impact and friction
on bodies which impede their progress. References to experiments
tending toward a distinction between effects of light and heat are
deficient. Ebermaier recommends that investigations into the effect
of light by the abstraction of heat be made on the sununit of high
mountains. He also differentiates between the heat of a hot, but dark,
stove and that of a flaming fire.

According to Horn, physical and chemical forces act differently
on living bodies and on dead bodies. The cause is the existence of a
basic force (vital force) in the first, which modifies those forces. Their
effects, however, are not to be traced solely to the irritability of the
body. Horn does not hesitate to draw comparisons between the effect
of light on plants and that on animals, since many analogies may be
established from both regarding origin, growth, maturity, and prop-
agation, as well as their reactions to the influence of the different
forces of nature. In both essays there are full details of the effects of
light: the generation of green color in plants, the development of “vital
air” (oxygen) from plants, the advancement of the cultivation and
full growth of plants, and on their photo-tropism and nutations. Horn
attributes particular importance to Senebier’s Memoires physico-chim-
iques de la lumiere solaire, pour modifier les etres des trois regnes de
lanature,et sourtout ceuxduregne vegetal (3 vols., 1782), which state
that light retards the decomposition and decay of organic substances
of plant and animal nature. He even speaks directly of the antiseptic
effect of light.

In Sotheran’s (1926) catalogue the annotator says of this work of
Senebier’s:

FROM VAUQUELIN TO DAVY 125

The author confirmed the discoveries of Ingenhousz and discovered the
fact that chlorophyll is bleached by the action of light. He also made im-
portant investigations on the action of light on resins and essential oils
and found that some of the former, on exposure to light, lose their solu-
bility ... in fact later utilized in the halftone process.

All the authors mentioned agree that light acts as a stimulant on
living organic bodies, which is particularly apparent on the surface of
the body, and this without taking into consideration the function of
the eyes, as is shown by the conduct of sightless animals in the light.
Where light is most intense on the earth, there the color of men and
animals is darkest. The color of many animals changes not only with
geographical latitude, but also with the seasons and the intensity of the
sun’s rays. Animals living in darkness are white.

Blumenbach explained the black pigment as hydrogen gas. The
hydrogen combines with the “vital air” (oxygen) of the atmosphere,
which on the one hand forms water, while on the other hand the car-
bon is precipitated in the malpighian layer below the epidermis.

According to Link the animal pigments are developed by vital
forces to which light contributes nothing, inasmuch as it acts as stim-
ulant. He noticed that desires increased the color of frogs and toads
even in the dark, while anger and fear, on the contrary, made their
color fade. Compare the celebrated experiments of E. Brucke with
chamelions. Heinrich calls attention to the fact that it is light, not heat,
which produces the dark pigmentation of the skin, and refers to the
accounts of the celebrated English philosopher Francis Bacon, Baron
Verulam, who determined that workmen in glassworks and furnaces
remain white ( Sylva sylvarum; seu, Historia nat., Cent, iv, p. 399).
This was a posthumous work of Francis Bacon, Baron Verulam, pub-
lished in 1627, a year after Bacon’s death.

The warmth of the skin effects an afflux of liquid secretion to the
vessels of the skin and increases their activity (the inspiratio and
exspiratio sanktoriana) ; light awakens and increases the vital energy,
elevates the frame of mind, and increases the pleasure for work. It is
interesting to determine, with reference to experiments lately pub-
lished, that Heinrich already differentiates between the heat sensation
which is caused in the body by the rays of the sun and the feeling
which the artificial heat of an oven creates in the body. Horn traces
the stimulating influence of light as properly due to the agency of
the eye, and he describes in detail the conjunction of the nerves of the

126 FROM VAUQUELIN TO DAVY

eye with other nerve systems. The detrimental consequences of the
lack of light on men and animals are discussed thoroughly, and the
weakness and sickliness of albinos are traced back to their lack of color-
ing, which causes them to be abnormally sensitive to light, and there-
fore they prefer to live in darkness. Ebermaier quotes an interesting
statement by the celebrated physicist Lichtenberg that life on earth
depends on the changes of the light intensity of the sun, its spots and
torches.

Horn and Ebermaier describe in detail the pathology of the effect
of light rays. Ebermaier knew of the following kinds of effect of light
rays: ( i ) redness of the skin, either painless or connected with itch-
ing, freckles; (2) inflammatory stage, sometimes with heat blisters
(these manifestations are the more intensive, the lighter the skin);
( 3 ) thickening and drying of the skin, which is inclined to stasis and
the formation of tumors; (4) sunstroke, due to the burning heat of sun
rays; (5) pellegra. Horn mentions injuries of the retina of the eye
(black cataract) and the increased irritability of the body (convulsion
of children) as consequences of excessive insolation. Ebermaier con-
tends that the exacerbations in certain diseases which take place in
the evening (exacerbatio vespertina) in wounds, abscesses, fever, in-
flammation of the eyes, fluxus coeliacus, dysentery, spastic conditions,
periodic vertigo, pain in the bones in scorbut and lues are due to the
absence of light. He quotes an old explanation of the morning “well
being”: “with the rising of the sun, disease itself takes flight.”

If the recitation of these numerous and interesting observations and
thoughts is fascinating, though they are not always expressed in the
sense of modern science, the hygienic and therapeutic expositions of
the two authors certainly must arouse our admiration. We find almost
completely outlined in these publications, which appeared one hundred
and thirty years ago and deserve a page of glory in the annals of the
University of Gottingen, the sphere of action in modern light therapy,
indications of results at which we have arrived with the aid of apparatus
and appliances for research which did not exist in those days.

Horn advanced the opinion that lack of light promoted much
stronger virulence in contagious diseases. He applied himself zealously
to the fight against living quarters which lacked light and air, quarters
under ships’ decks, rooms in hospitals, prisons, or convents, against nar-
row streets, with high houses and small windows— all of which impair
the state of health of whole classes of people, and he traced the high

FROM VAUQUELIN TO DAVY 127

mortality in cities to these evils. According to Ebermaier, the moderate
altitudes of the mountains are the most advantageous to health, partly
on account of the prevailing great light intensity, partly owing to
the high oxygen content of the air, qualified by the influence of light
on the vegetation, which is there so luxuriant. It is true that on the
highest levels the air is lacking in water vapor and the light intensity
is greatest, but the air there is too rarified and proportionally lacking
in oxygen. In the lower levels there is a good deal of vegetation, but
the oxygen content is, nevertheless, low on account of the small light
intensity. This is caused by the absorption of light by the vapors in
the atmosphere, which also contaminate the air. Although Ebermaier
and Horn, in attributing to light so great a hygienic importance, follow
largely the footsteps of Hufeland and other prominent physicians of
the time, it is certain that their recommendations of light as a curative
treatment for disease were greatly in advance of their era. Horn recom-
mends exposure to light, and quite explicitly' to full sunlight, for all
diseases which have their origin in a weakened condition and in the
inability to create sufficient stimulation of energy, especially in the
case of scrofula. Ebermaier mentions a cure of old abscesses in 1776,
and particularly that of a cancer of the lower lip, where La Payre ap-
plied concentrated sun rays through a burning glass to the lip. He re-
ports that Le Comte, after repeating these operations, noted that it was
notthe burning (heat) which was to be considered of such great impor-
tance, because the procedure gave better results in the winter, when the
sun was not so hot as in the summer ( Histoire de la Societe Roy ale de
Medecine, 1776, Paris, 1779, p. 298).

Since light increased the secretions, he recommended it for the
treatment of gout, podagra, and advanced cases of rheumatism. Its
use is indicated for hypochondria and its attendant atonic conditions
of the stomach and intestines and for symptoms due to age and con-
sumption. The treatment of rickets by light therapy, believed to be an
achievement of research in most recent years, was already expressly
indicated by Ebermaier in a special chapter. For many psychoses this
treatment seems to deserve consideration. On the contrary, Horn
warns against the use of light treatment in cases of generally aggravated
irritability and sensitiveness.

And so one finds— as Professor Leopold Freund stresses— in these
forgotten publications rich and valuable material which will abundant-
ly repay our study.

128 FROM VAUQUELIN TO DAVY

SIR WILLIAM HERSCHEL DISCOVERS (l8oo) THE INFRARED SPECTRUM;

J. W. RITTER DISCOVERS (l8oi) THE INVISIBLE ULTRAVIOLET RAYS

AND THEIR ACTION ON CHLORIDE OF SILVER AND IS THE FIRST TO OB-
SERVE THE ANTAGONISTIC EFFECT OF RED AND VIOLET RAYS

At the turn of the eighteenth century the celebrated English astron-
omer Friedrich Wilhelm Herschel (1738-1822) occupied himself with
experiments on the unequal proportion of heat in the prismatic solar
spectrum and discovered the invisible infrared heat rays ( Philosophical
Transactions, 1800, pp. 2, 255; also Gilbert’s Annals, 1801, p. 137) .This
correct observation, which was at first disputed, gave great stimulus
to a further study of the spectral properties of light.

On the other hand, J. W. Ritter discovered (1801) the ultraviolet
rays. Ritter (1776-1810), when fifteen years old, came to Liegnitz
as apothecary’s assistant, he remained there for five years. He lived then
in Jena, Gotha, and Weimar, where he made important investigations
in the field of galvanic electricity, during which he discovered gal-
vanic polarization and invented the storage column (predecessor of
the accumulator) and so forth. Worthy of notice is his essay Beweis,
dass ein be standi ger Galvanismus den Lebensprozess im Thierreich
begleitet (1798). For us his discovery of the ultraviolet rays is of
special importance.

Ritter first published his discovery of the invisible violet rays on
February 22, 1801, in the Intelligenzblatt der Erlanger Liter atur-
zeitung (1801 ), No. 16. 15 When he covered paper with damp, freshly-
prepared chloride of silver and let the solar spectrum act on it in a
dark room, he saw that the action began first beyond the ultraviolet
and only then proceeded toward the violet. He not only discovered
the decomposition of silver chloride in ultraviolet but also noted that
silver chloride paper, which previously in diffused daylight had turned
dark but slightly, became darker in the violet end of the spectrum,
but lighter in the red end, which observation first pointed to the
antagonism of the chemical effect of violet and red lights. He found
“that the darkening did not occur beyond the green and that the light-
action in the orange and red produces a true oxidation of the already
reduced silver chloride or, what amounts to the same thing, in retard-
ing or suspending the reduction.” The violet and red of the spectrum,
when mixed under a burning glass, reduce the silver chloride, “which
demonstrates that the reducing rays must be present to a far greater
degree in white light than those which oxidize.” From this follows the

FROM VAUQUELIN TO DAVY 129

classification of the more or less refrangible regions of the spectrum
into a “reducing region and an oxidizing region.” This, however, was
later contradicted.

FURTHER ADVANCES IN PHOTOCHEMISTRY— WOLLASTON INTRODUCES,

IN 1802, THE NAME “CHEMICAL RAYS” FOR THE MORE REFRANGIBLE

RAYS

In the same year Leroux made the statement— it seems, without
having had knowledge of Abildgaard’s publication— that a bottle filled
with red oxide of mercury would turn black on the side facing the
light because of deoxidation. 18 At exactly the same time Robert Harup
also published his results. 17 He claimed to have studied as early as 1797
the influence of light on mercury compounds. He stated that mercury
oxide and calomel were reduced on exposure to sunlight and that this
phenomenon also took place in a hermetically sealed glass tube. Both
Leroux and Harup, however, must cede the priority for this statement
to Abildgaard, who had published his work a year earlier. 18

In 1801 appeared a booklet, which has now become very rare, by
Christian Samuel Weiss: Betrachtimg eines merkwiirdigen Gesetzes
der F arbenanderung organischer Korper durch den Einfluss des Lich-
tes (Leipzig, 1801). He points out that the change of color which
organic matter suffers in light is opposite to that which is observed in
inorganic bodies. 18 Weiss also proposes a peculiar view on colors. He
assumes that light is composed of several basic light substances which
specifically differ from each other; colored matter reflects light with
which it “has no chemical (!) affinity”; for instance, red bodies, which
show no affinity for red light, reflect red light, but absorb all other light
(rays). Weiss thus traces back all pure optical color phenomena to
chemical affinities of light and so oversteps the mark in the exposition
of his chemical theory of light. The color change of a body in light
Weiss regarded as the change of its chemical
dent light.

Therefore, when a substance, which has been exposed to light, thereby
changes its affinity for the free substance of light, there can be no other
change than that of the further penetration of the light-substance accord-
ing to chemical laws, that is to say, greater saturation of the light-sub-
stance— in so far as the substance does not undergo other condition of
mixture. An inorganic substance (without vitality) will, when it changes
nothing but its color through light, necessarily show less affinity to free

affinity to the free inci-

i 3 o FROM VAUQUELIN TO DAVY

light after it has been exposed to light for a while than before. Conse-
quently, it will reflect more light than before, that is, its color will grow
lighter, it will bleach [[bleaching of linen, bones, etc.]. ... It is entirely
different in living organic nature. . . . The laws are opposite to those of
dead matter. Here the affinity is increased by the influence of light. The
more the living body of animal or plant is exposed to light, the more its
color deepens, the more it is able to absorb the substance of light. . . .
Light acts as an exciter on the vital forces of the organs and, as a conse-
quence, the secretions of the pigment show changes on the surface. The
pigment receives a special mixture, which increases its affinity to free light
substance. . . . This stimulus may be of a mechanical nature— either ac-
cording to Newton’s or Euler’s system— always the illuminated substance
will be moved. Light can also influence living organisms by chemical
stimulus, so that the “light stuffs” can combine also with organic matter.

I have reproduced Weiss’s views extensively here, because one may
discern perfectly from them the spirit of the theories prevailing at that
time. We find on the one hand that they adhere strictly to the view
of “light matter,” which can combine or separate and, in itself, is
already explained as combined matter; on the other hand, we find
prophetic anticipations of later scientific results, which present the
opinion that light action can be both mechanical and chemical. This
rigid classification, with which the scholars of those days insisted that
dead matter be treated separately from living matter (the dissertation
on “vital force” which cancels or reverses all chemical laws on matter) ,
appears precisely expressed in Weiss’s theory.

It is interesting to note the discovery of Desmortiers, 20 also made in
1801, that Prussian blue loses its color and turns white when air is
excluded, that is, when stirred up together with nut oil and covered
with water, but regains its color immediately in the air. 21 He proposed
the following conclusions: ( i ) The loss of color does not result from
the decomposition of the oil, but from a change in the surface, and is
caused by the matter sinking to the bottom and the extinction of the
light corpuscles in the small leaves and between the interstices of the
coloring substance. (2) For the recovery of the color neither air nor
any of its component parts nor an outside admixture is necessary; it
can be achieved equally as well in an air-tight chamber. ( 3 ) Heat in the
absence of light impedes and even destroys the color. A slight internal
motion of its particles, no matter how effected, restores the color faster
or slower, in proportion to the strength of light and the force of motion

FROM VAUQUELIN TO DAVY 131

applied. This discovery is often credited to Chevreul (1849), although
Desmortiers made this statement forty-eight years earlier.

Scheldracke purified the fat oils (linseed oil, nut oil, poppy oil) of
their mucilage by the action of sunlight, to which he exposed them
in long-necked bottles. 22

Shortly after Ritter’s publication, William Hyde Wollaston an-
nounced, in 1802, certain observations regarding the chemically active
but invisible rays of the solar spectrum, which are here quoted from
his “Method of Examining Refractive and Dispersive Powers by Pris-
matic Reflection” in Royal Society, Philosophical Transactions (1802,
P- 379 )-

Although what I have described above comprises the whole of the
prismatic spectrum that can be rendered visible, there also pass on each
side of it other rays, whereof the eye is not sensible. From Dr. Herschel’s
experiments ( Philosophical Transactions, 1800), we learn, that on the one
side there are invisible rays occasioning heat, that are less refrangible than
red light; and, on the other, I have myself observed (and the same remark
lias been made by Mr. Ritter), that there are likewise invisible rays of an-
other kind, that are more refracted than the violet. It is by their chemical
effects alone that the existence of these can be discovered; and by far the
most delicate test of their presence is the white muriate of silver.

T o Scheele, among other valuable discoveries, we are indebted for having
first duly distinguished between radiant heat and light ( Traite de l’ air et
du feu, pp. 56-57); and to him also we owe the observation that, when
muriate of silver is exposed to the common prismatic spectrum it is black-
ened more in the violet than in any other kind of light. In repeating this
experiment I found that the blackness extends not only through the space
occupied by the violet, but to an equal degree, and to about an equal dis-
tance, beyond the visible spectrum; and that by narrowing the pencil of
light received on the prism, the discoloration may be made to fall entirely
beyond the violet.

It would appear, therefore, that this and other effects, usually attributed
to light, are not in fact owing to any of the rays usually perceived, but to
invisible rays that accompany them; and that, if we include two kinds that
are invisible, we may distinguish, upon the whole, six species of rays into
which a sunbeam is divisible by refraction.

He then called for the first time the most refrangible rays of the
spectrum “chemical rays,” which designation they retained later, and
he insisted on this characterization emphatically, particularly because
he did not agree with Ritter’s classification of oxidizing and reducing

1 32 FROM VAUQUELIN TO DAVY

rays. 23 Wollaston knew in 1802 that gum guaiacum was strongly
affected by violet rays and suffered an oxidation from their action,
while according to Ritter the violet rays merely exerted a reducing
action. Wollaston’s statements made at that time are in no manner so
exhaustive as those of Ritter, and it was not until several years later
that Wollaston came forward with additional details.

William Hyde Wollaston, M.D., F. R. S. (1766-1828), was an emi-
nent English chemist and physicist. He studied medicine at Cambridge,
received his doctor’s degree, went to London, gave up the practice of
medicine in 1800, and devoted himself with great success to chemistry
and physics. His discoveries were of great importance not only to
science but also to industry and the arts. He found the malleability of
platinum, discovered the elements palladium and rhodium in platinum
ore, made investigations in the field of galvanic electricity, perfected
the microscope and “camera lucida,” and invented the improved
chromatic meniscus lens named after him, July 12, 1812, the concave
side of which faced the object. This was of great advantage and was
probably the reason why Niepce as well as Daguerre made use of
this type of lens, manufactured by the Paris optician Chevalier (Eder’s
Handbuch, Vol. I, Pt. 4, Photo. Objektive, 191 1). Wollaston was also
the first to observe the dark lines in the solar spectrum, which were later
more definitely determined by Joseph von Fraunhofer.

After many years of painstaking attempts to mark exact measure-
ments of the refraction and dispersion of prisms which he had under
consideration, Fraunhofer employed successfully, about 1814-1815,
the dark lines of the solar spectrum which were observed first, more
that a dozen years earlier by Wollaston, for the purpose of determining
the refractive and diffractive powers of prisms, without confining him-
self to the complicated and precise method of his experiments. The
importance of this method was tacitly recognized by the leading
opticians everywhere, by calling these lines, not after their first dis-
coverer, but after the scientist who first applied them in a practical
way. This complete solution of the problem for the measurement of
prisms was used by Fraunhofer in a twofold way (M. v. Rohr) .

Joseph von Fraunhofer (1787-1826) was to have become a glazier.
At the age of twelve he entered the employment of the glass cutter
Weichselberger in Munich, who also made mirrors, as an apprentice.
The fact that young Fraunhofer was luckily saved from underneath
the debris when his master’s house collapsed in 1801 attracted the

FROM VAUQUELIN TO DAVY 133

attention of King Maximilian Joseph of Bavaria, who, after he had
recovered, made him a present of eighteen ducats. With this money
Fraunhofer purchased a glass-grinding machine, which he used for
grinding optical glasses. He studied optical and mathematical literature
with particular attention to the laws of refraction of light. In 1 807 he
became assistant in, and later partner of, the important optical work-
shop of Georg von Reichenbach, J. Utzschneider, and J. Liebherr in
Benedictbeuem, in Bavaria. From 1818 Fraunhofer conducted the
optical works, which had become very famous, and he moved it to
Munich, where, in 1817, he became a member of the Akademie der
Wissenschaften and was knighted in 1818. Unfortunately, he died at
the age of thirty-nine from an old lung trouble.

Fraunhofer’s greatest achievements are the improvement of the
telescope and other optical instruments. At first he invented a machine
for polishing large, mathematically accurate, spherical surfaces; he
began, in 1 8 1 1 , the manufacture of a flint glass which by far surpassed
in quality and usefulness the English flint glass. During the years 1814
to 1817 the fixed dark lines in the solar spectrum were first accurately
determined by him and used for the measurement of the refraction
and dispersion of his optical glass. These “Fraunhofer lines” became
of particular importance for spectroanalysis. He further discovered
the grating spectrum by the use of parallel lines ruled in glass and
deduced its laws. His investigations made possible the calculation of
almost completely achromatic lens combinations. His dioptric tele-
scopes laid the foundation for the world-wide reputation which his
optical institute at Munich enjoyed. He also invented the heliometer
which made possible the measurement of the diameters and of the
distances between the sun and the planets. Fraunhofer was one of the
greatest mathematical and practical opticians the world has produced.

Rumford’s statement 24 “that all those visible changes which are pro-
duced in bodies by exposure to the action of the sun’s rays are effected,
not by any chemical combination of the matter of light with such
bodies, but surely by the heat which is generated, or excited, by the
light that is absorbed by them” encouraged Harup, in 1 802 , 25 to experi-
ment with mercury salts, and he satisfied himself that sunlight effects
the blackening of mercuric oxides when they are placed in a transparent
glass vessel, but not in an opaque glass. He found also that when air
is admitted, and in the presence of moisture, the change in light was
not noticeably advanced and that light (not heat) acted always only on

i 3 4 FROM VAUQUELIN TO DAVY

the surface. Harup, in order to further clarify Rumford’s assertions, at-
tempted to reduce in light minium and acetate of lead (pure, as well
as mixed with carbon) , but without success. He concluded from these
experiments that light has a specific action which differs from the
effect of heat.

THE LUNAR SOCIETY IN LONDON AT THE TURN OF THE EIGHTEENTH
CENTURY AND THOMAS WEDGWOOD

The statement that photography had been supposedly invented at
the end of the eighteenth century (about 1791) by Watt and his col-
laborator Boulton attracted a great deal of attention in 1863. It was
recalled that a society existed at that time in Birmingham, called the
“Lunar Society,” which numbered among its members Josiah Wedg-
wood, Watt, Priestley, and others (Kreutzer’s Zeitscbr. f. Phot.,

1863, VII, 129; Phot. News, 1863, VII, 407; Bull. Soc. frang d. phot.,

1864, XIII, 81). The Birmingham Daily Post printed the news on
April 16, 1863, that photographs were found there of the nearby
factory town of Soho, which showed the buildings as they appeared
at the end of the eighteenth century. This seemed from the start
improbable and very unlikely of proof, since, as a matter of fact, neither
Josiah Wedgwood, the potter, nor his son “Tom” Wedgwood was
familiar in 1 802 with the fixing of photographic printing process, nor
could James Watt have known very much of a photographic printing
process, or he would not have cited the common use of copying ink
when he described, about 1802, the method of copying letters ( Das
Neueste und Nutzlichste in der Che-mie . . . 1802, V, 124). In fact,
these supposedly old pictures later proved to be daguerreotypes and
Talbotypes of later date.

This statement originated in a curious misunderstanding arising from
ignorance of the purpose and proceedings of this “Lunar Society.”
The society had nothing whatever to do with the study of light or
photographic processes; it consisted of a small but select number of
prominent scholars and engineers interested in the natural sciences. 20
The “Lunar Society” derived its name from their meeting, which took
place on the Monday of each month after the full moon “in order to
partake of the joy of going home in daylight.” At that time there were
only eight or ten members, among them, it is interesting to note,
Josiah Wedgwood, the potter, the Reverend Joseph Priestley, cele-
brated gas analyst, James Watt, inventor of the steam engine, Matthew

FROM VAUQUELIN TO DAVY 135

Boulton, a partner of Watt, Dr. Erasmus Darwin, grandfather of
Charles Darwin, William Murdoch, inventor of coal-gas lighting and
financial backer of Watt and Boulton, William Herschel, the founder
of stellar astronomy.

The meetings of the “Lunar Society” were held at the home of
J osiah W edgwood (1730-1795), at Etruria, England, and we know that
young Thomas Wedgwood was keenly interested in the discussions
of the society. It is probable that there he first learned of the chemical
action of light on silver, since the chemist Priestley was familiar with
the experiments of Schulze and others, as related in his History and
Present State of Discoveries Relating to Vision, Light and Colours
077 2 )-

There were also, as mentioned on an earlier page, the notebooks of
Lewis on the blackening of nitrate of silver on leather, and so forth,
which were owned by the Wedgwood family, and finally there was
Chisholm, the former assistant of Lewis, the tutor and teacher of
Thomas Wedgwood, son of Josiah. This gives a perfect picture of
the bond which connected the work of Schulze and Thomas Wedg-
wood. It may be supposed that Thomas Wedgwood began his photo-
graphic experiments in 1 790, at nineteen; we shall report these later.
Many writers suppose that his father, Josiah Wedgwood, made ex-
periments of his own in photography; but this is contradicted by the
fact that he died in 1 795, seven years before the publication by his son
of the work discussed above.

THOMAS WEDGWOOD PUBLISHED IN 1802 HIS INVENTION OF THE METHOD
OF REPRODUCING DRAWINGS ON GLASS WITH SILVER NITRATE OR SILVER
CHLORIDE; HE PRODUCED IN SUNLIGHT PHOTOGRAPHIC PROFILES AS
SILHOUETTES; DAVY MAKES PUBLIC IN THE SAME YEAR THE METHOD
FOR THE PRODUCTION OF PHOTOGRAPHIC ENLARGEMENTS BY THE AID
OF THE SOLAR MICROSCOPE

Thomas Wedgwood (1771-1805), fourth son of the potter Josiah
Wedgwood, was from early childhood disposed to infirmity and ill-
ness. He traveled a great deal, interested himself in different scientific
investigations, and astonished the learned society in 1 802 by the publi-
cation which later became so important to the history of photography.

A family history of Wedgwood appears in R. B. Litchfield’s work
Tom Wedgwood, the First Photographer; an account of his life, his
discovery and his friendship with Samuel Taylor Coleridge, including

1 36 FROM VAUQUELIN TO DAVY

the letters of Coleridge to the Wedgwoods . . . 27 (London, 1903).
In 1802 Thomas Wedgwood, together with Humphry Davy, pub-
lished the dissertation “An Account of a Method of Copying Paintings
upon Glass and of Making Profiles by the Agency of Light upon
Nitrate of Silver, invented by T. Wedgwood, Esq., with observations
by H. Davy,” Journal of the Royal Institution, London (I, 170). Tom
Wedgwood was at that time twenty-nine; Davy 28 only about twenty-
three years old.

White paper, or white leather, moistened with solution of nitrate of
silver, undergoes no change when kept in a dark place; but on being ex-
posed to the daylight, it speedily changes colour and, after passing through
different shades of grey and brown, becomes at length nearly black.

The alterations of colour take place more speedily in proportion as the
light is more intense. In the direct beams of the sun, two or three minutes
are sufficient to produce the full effect. In the shade, several hours are re-
quired, and light transmitted through different coloured glasses acts upon
it with different degrees of intensity. Thus it is found that red rays, or the
common sunbeams passed through red glass, have very little action upon
it: Yellow and green are more efficacious, but blue and violet light produce
the most decided and powerful effects.*

The consideration of these facts enables us readily to understand the
method by which the outlines and shades of paintings on glass may be
copied, or profiles of figures procured, by the agency of light. When a
white surface, covered with solution of nitrate of silver, is placed behind
a painting on glass exposed to the solar light, the rays transmitted through
the differently-painted surfaces produce distinct tints of brown or black,
sensibly differing in intensity according to the shades of the picture, and

•The facts above mentioned are analogous to those observed long ago by Scheele,
and confirmed by Senebier. Scheele found that in the prismatic spectrum the effect
produced by the red rays upon silver muriate was very faint, and scarcely to be per-
ceived; while it was speedily blackened by the violet rays. Senebier states that the time
required to darken silver muriate by the red rays is twenty minutes; by the orange,
twelve; by the yellow, five minutes and thirty seconds; by the green, thirty-seven
seconds; by the blue, twenty-nine seconds; and by the violet, only fifteen seconds.—
Senebier, Sut la lunriere, III, 199.

Some new experiments have been lately made in relation to this subject, in con-
sequence of the discoveries of Dr. Herschel concerning the invisible heat-making
rays existing in the solar beams, by Dr. Ritter and Bockmann in Germany and Dr.
Wollaston in England.

It has been ascertained by experiment upon the prismatic spectrum that no effects
are produced upon the muriate of silver by the invisible heat-making rays which exist
on the red side and which are least refrangible, though it is powerfully and distinctly
affected in a space beyond the violet rays, out of the boundary. See Annalen der
Pbysik (VII, 517.— D).

FROM VAUQUELIN TO DAVY 137

where the light is unaltered, the colour of the nitrate becomes deepest.

When the shadow of any figure is thrown upon the prepared surface,
the part concealed by it remains white, and the other parts speedily become
dark.

For copying paintings on glass, the solution should be applied on leather;
and in this case it is more readily acted upon than when paper is used.

After the colour has been fixed upon the leather or paper, it cannot be
removed by the application of water, or water and soap, and it is in a high
degree permanent.

The copy of a painting, or a profile, immediately after being taken,
must be kept in some obscure place. It may indeed be examined in the shade,
but in this case the exposure should be only for a few minutes; by the light
of candles and lamps, as commonly employed, it is not sensibly affected.

No attempts that have been made to prevent the uncoloured part of the
copy or profile from being acted upon by light have as yet been successful.
They have been covered with a thin coating of fine varnish, but this has
not destroyed their susceptibility of becoming coloured; and even after
repeated washings, sufficient of the active part of the saline matter will
still adhere to the white parts of the leather or paper, to cause them to
become dark when exposed to the rays of the sun.

Besides the application of this method of copying that has just been
mentioned, there are many others. And it will be useful for making delinea-
tions of all such objects as are possessed of a texture partly opaque and
partly transparent. The woody fibres of leaves and the wings of insects,
may be pretty accurately represented by means of it, and in this case, it
is only necessary to cause the direct solar light to pass through them, and
to receive the shadows upon prepared leather.

When the solar rays are passed through a print and thrown upon pre-
pared paper, the unshaded parts are slowly copied; but the lights trans-
mitted by the shaded parts are seldom so definite as to form a distinct
resemblance of them by producing different intensities of colour.

The images formed by means of a camera obscura have been found too
faint to produce, in any moderate time, an effect upon the nitrate of silver.
To copy these images was the first object of Mr. Wedgwood in his re-
searches on the subject, and for this purpose he first used the nitrate of
silver, which was mentioned to him by a friend, as a substance very sensible
to the influence of light; but all his numerous experiments as to their
primary end proved unsuccessful.

In following these processes, I have found, that the images of small
objects, produced by means of the solar microscope, may be copied without
difficulty on prepared paper. This will probably be a useful application
of the method; that it may be employed successfully, however, it is neces-
sary that the paper be placed at but a small distance from the lens.

1 38 FROM VAUQUELIN TO DAVY

With regard to the preparation of the solution, 1 have found the best
proportions those of one part of nitrate to about ten parts of water. In
this case, the quantity of the salt applied to the leather or paper will be
sufficient to enable it to become tinged, without affecting its composition,
or injuring its texture.

In comparing the effects produced by light upon muriate of silver with
those produced upon the nitrate, it seemed evident that the muriate was the
most susceptible, and both were more readily acted upon when moist than
when dry, a fact long ago known. Even in the twilight, the colour of moist
muriate of silver spread upon paper slowly changed from white to faint
violet; though under similar circumstances no immediate alteration was pro-
duced upon the nitrate.

The nitrate, however, from its solubility in water, possesses an advan-
tage over the muriate; though leather or paper may, without much diffi-
culty, be impregnated with the last substance, either by diffusing it through
water, and applying it in this form, or by immersing paper moistened with
the solution of the nitrate in very diluted muriatic acid.

To those persons not acquainted with the properties of the salts con-
taining oxide of silver, it may be useful to state that they produce a stain
of some permanence, even when momentarily applied to the skin, and in
employing them for moistening paper or leather, it is necessary to use a
pencil of hair, or a brush.

From the impossibility of removing, by washing, the colouring matter
of the salts from the parts of the surface of the copy which have not been
exposed to light, it is probable that, both in the case of the nitrate and
the muriate of silver, a portion of the metallic acid abandons its acid to
enter into union with the animal or vegetable substance, so as to form with
it an insoluble compound. And, supposing that this happens, it is not im-
probable, but that substances may be found capable of destroying this
compound, either by simple or complicated affinities. Some experiments on
this subject have been imagined, and on account of the results of them may
possibly appear in a future number of the Journal. Nothing but a method
of preventing the unshaded parts of the delineation from being coloured
by exposure to the day is wanting, to render the process as useful as it is
elegant.

Davy remarks, at the end of his report, that he will refer again to
this subject in one of the following issues of the above-mentioned
journal; but neither Wedgwood nor Davy published any other state-
ment about this matter.

The invention of the production of photographic copies of drawings
on glass and of silhouettes in sunlight on silver nitrate paper is often

FROM VAUQUELIN TO DAVY 139

attributed to the joint work of Wedgwood and Davy, although the
credit for it belongs to Wedgwood alone.

The fundamental importance of Wedgwood’s work lies in the fact
that he was the first to visualize the possibility of obtaining a perma-
nent image with the aid of the camera obscura, but his efforts remained
unsuccessful. Sir Humphry Davy (1778-1829) was president of the
Royal Society in London from 1820 to 1827. He is the founder of
electrochemistry, discoverer of potassium, sodium, the alkaline earths
metals (barium, strontium, calcium), and magnesium. He discovered in
1810 that chlorine is an element and that muriatic acid is a compound
of chlorine and hydrogen, and he studied the reaction to light of
chlorine with hydrogen and carbon monoxide. As inventor of the
miner’s safety lamp, named after him, his name became known every-
where. For the history of photography, his initial production of iodide
of silver and the recognition of its sensitiveness to light (1814) are of
particular interest, because both Daguerre and Niepce worked with
silver iodide, and Talbot learned of Davy’s discovery in 1834, as he
recounts in his book The Pencil of Nature (1844).

The immortal fame of Thomas Wedgwood rests on his invention of
the idea and method of reproducing designs on glass, on silver nitrate
paper, and on silver chloride paper, that he was the first photographer
in the world, and that he copied silhouettes on paper in sunlight. Davy
was the first to give out a statement, in 1802, on the production of en-
larged images by means of the solar microscope. In this publication
is also found for the first time accounts of the production of silver
chloride paper by successive applications of silver nitrate and of chlo-
ride solutions on leather and paper, all of which served as a starting-
point for the later method of Talbot. True, neither Wedgwood nor
Davy found a medium for fixing these light images on silver-paper,
and it is probable that they made no efforts in that direction. Thomas
Wedgwood’s ill health seems to have interfered with his further' labors;
but he never allowed anything to be known about his illness, and he
died three years after the publication of his record-making invention.
Humphry Davy seems to have paid no further attention to the matter,
but had withdrawn entirely from the field of photography, owing to
his electro-chemical experiments and discoveries, which were so extra-
ordinarily important in the development of chemistry. Had the gifted
Davy interested himself in the fixation of silver images, he would
surely have found the point of contact in the publication of Scheele,

1 4 o FROM VAUQUELIN TO DAVY

which he himself had quoted, where it is stated clearly and precisely
that ammonia liberates the silver chloride from the photochloride,
blackened by light, and that it precipitates the black metallic silver
formed by the action of light. Thus, an efficient fixative would have
been found; but no one paid any attention to it.

The publication of Wedgwood and Davy of 1802 was soon lost
in obscurity. It was not until thirty-seven years later that Arago un-
covered it in his presentation of the report on the daguerreotype process
before the French Academie des Sciences in 1839; at that time the two
Englishmen were proclaimed the forerunners of photography.

It is impossible, however, for the impartial historian to award the
priority for the first invention of photography to these two gentlemen,
notwithstanding the full appreciation of their enormous services, and
they must be placed in the ranks of those pioneers in the field of photo-
chemistry who developed and practically applied, after more or less
intensive preparatory studies, facts already known. 20

The sensitiveness to light of silver-nitrate-chalk paste was discovered
by Schulze in 1727; that of silver chloride by Beccarius in 1757. Hellot
learned of the changes effected by light on paper impregnated with
silver nitrate in 1737, and Scheele of light action on paper coated with
chloride of silver (1777). Senebier, in 1782, continued like his pre-
decessor Scheele to differentiate between the action of colored light.
Schulze and Beccarius demonstrated that writing and designs could
be copied on silver chloride, by allowing light to proceed through
the stencils made from opaque materials, and Wedgwood found that
leaves and designs on glass could be employed as well as stencils, while
Davy inserted microscopic objects in a solar microscope, and projected
them on sensitized paper some distance away, and thus invented ( 1 802 )
the projection of images by photography, which includes the photo-
graphic enlarging process.

The application of the light-sensitive silver-salt papers to the copy-
ing of leaves, silhouettes, and designs on glass, and Wedgwood’s idea
of copying images in the camera were ingenious, but they could not
carry their ideas to full realization. Notwithstanding these and the
illustration of the enlargements of the solar microscope by Davy, ser-
vices for which we must ever preserve a grateful memory, we must
not conceal the fact that both Wedgwood and Davy forgot or did not
know of that important discovery of old Scheele, namely, that white
chloride of silver is completely soluble in ammonia, which is difficult

FROM VAUQUELIN TO DAVY 141

to understand, because Scheele’s writings were widely distributed,
and an English translation had been published. From Scheele they
could have learned of a fixative for the silver chloride images, which
Davy expressly declared had not been discovered. This neglect of his
predecessor’s labors on the part of Davy had serious consequences for
the development of photography. Davy’s announcement that he would
deal more exhaustively with the question of the fixation of light images
and his failure to produce results of any sort discouraged his con-
temporaries from trying to seek the solution of a problem which a
scientist of Davy’s rank found to be beyond his ability, and so years
passed before the fixation of silver images was accomplished.

THE SILHOUETTES OF THE PHYSICIST CHARLES

In Arago’s first report on the daguerreotype, which he presented to
the Academie des Sciences on August 19, 1839, we find the statement
that the first traces of the art of reproducing light images as silhouettes
on light-sensitive paper are met with in the first years of the nineteenth
century.

About this time [Arago continues:] our countryman Jacques Alexandre
Cesar Charles made use of a coated paper in order to produce silhouettes
by the aid of sunlight. Charles died without describing the preparation he
used, and since the historian must support his statements with printed and
authentic documents, it becomes necessary in all fairness to trace back to
Wedgwood the basic invention of the new art.

Another reason for protesting against the mention of Charles in con-
nection with this invention is our inability to discover anywhere the
year in which Charles’s experiments took place. For many years Charles
delivered private lectures on experimental physics in Paris; he died
in 1823. Unfortunately, Arago made his statement in such an ambigu-
ous manner that one is involuntarily led to the conclusion that Charles
had photographed his silhouettes before Wedgwood, at any rate, one is
kept completely in the dark on the point of time of his experiments.
It is true that Gaston Tissandier states, in his Les Merveilles de la photo-
graphie (Paris, 1874, p. 15), that Charles, “about 1780,” employed
the camera obscura for rudimentary photography, projecting sil-
houettes of persons on paper coated with silver chloride. Tissandier
presents an illustration on page 14 of his Les Merveilles, in order to
demonstrate how the procedure may have been enacted.

It must be expressly stated here, however, that this illustration has its

FROM SAGE TO GAY-LUSSAC

142

origin in the imagination of Tissandier and that the year 1780, alleged
to be that of the demonstration by Charles, is not supported by any
mention of the source; it probably originated also in a dream of the
author, just as did the illustration. I beg leave to propose the following
presumption: Charles simply had read Davy’s account of Wedgwood’s
experiments, followed them, and from them delivered a lecture on
the subject, accompanied by an experiment, “in the first years of the
nineteenth century.” This explanation at once does away with all
secrets concerning Charles’s proceedings. His connection as member
and librarian of the Paris Academie des Sciences excludes the accept-
ance of any secret mongering.

Jacques Alexandre Cesar Charles (1742-1822) was a French physi-
cist and popular lecturer on experimental science in Paris about 1780;
professor of physics at the Conservatoire des Arts et Metiers, Paris,
member and for some years librarian of the Institut de France, in the
library of which institution he doubtless had access to the Journal of
the Royal Institution of London, wherein Wedgwood and Davy re-
ported (1802) their experiments in photography on silver chloride
paper. After Montgolfier’s discovery of ballooning, Charles was the
first to use hydrogen to inflate balloons (1783), and he was actually the
first man who ventured to ascend alone in a free balloon. In literary
circles he was well known as the husband of “Elvire,” the heroine of
some of Lamartine’s poems.

Chapter XVI. THE STUDIES OF SAGE (1803),

LINK, AND HEINRICH ON THE NATURE OF LIGHT

(1804-8) UP TO GAY-LUSSAC AND THENARD (1810)

Balthazar George Sage (1740-1842) was apothecary at the Hotel
des Invalides, Paris, 1778, professor of assaying and metallurgy in the
Paris Mint and member of the Academy of Sciences in Paris. He
worked a great deal on chemical analysis, the chemistry of metals and
mineralogy in general. He lost his eyesight in 1805.

The light-sensitivity of natural realgar (arsenic disulphide) was first
noted by Sage in 1803. Sage observed this phenomenon on one of those
miniature pagodas which the Chinese make from this mineral for ex-
port as decorative novelties; when polished, they show a beautiful

FROM SAGE TO GAY-LUSSAC

i43

blood-red color. He noticed that the tiny pagoda lost its luster and
brilliant red color in the parts directly touched by light, and took on
an orange-yellow coating which fell off easily (so-called weathering) ;
where the light did not strike it, the original vivid coloring remained
unchanged. Realgar is found at Solfatara in octahedric crystals, a ruby
red orpiment which takes on an orange-yellow coating in light. 1 This
phenomenon belongs to the domain of physics, being a change of the
molecular state, not a photochemical reaction proper.

In 1 803 the apothecary Pierre Francois Guillaume Boullay described
the decomposition of bichloride of mercury in light. A concentrated
solution of this salt in water decomposed after exposure to sunlight
for several days, the liquid giving off some oxygen and taking on the
red color of litmus, which indicated the formation of free acid
(muriatic acid); some of the bichloride of mercury crystals lost their
transparency and were no longer completely soluble in water. After
prolonged light action a gray precipitate settled. 2

In the same year Johann Quirin Jahn, member of the Kais. Akademie
der bildenden Kiinste, at Vienna, published a dissertation on “The
Bleaching and Purification of Oils for Oil Painting” (1803), in which
he states that linseed oil clarifies in sunlight and is bleached still more
by the heat of the sun. There is no specific light action mentioned
anywhere, but sunshine is identified with warm weather.

Berthollet, in 1803, renewed his interest in the development of
photochemistry. In his celebrated Essay de statique chimique various
photochemical reactions are mentioned, and new hypotheses are
offered for their explanation.

“The heat substance” Berthollet states, “differs from light in that it
is much lighter in weight and also absorbed by any matter which trans-
mits light .... There are several chemical compounds which seem
to be effected differently by heat and by light, which leads to the
conclusion that these are to be considered as dissimilar.” As proof,
Berthollet cites chlorine water and nitric acid; concerning yellow
prussiate of potash he remarks that it decomposes in the sun with for-
mation of hydrocyanic acid and separation of a blue precipitate.

He published also new experiments on silver chloride. This com-
pound, when exposed to light under water, imparted an acid reaction
to the water and contained muriatic acid, but no chlorine. The gas
which escapes at first is not oxygen, as he had stated in 1786, but simply
air. “My assumption,” he continues, “was unfounded that in this case

FROM SAGE TO GAY-LUSSAC

144

the oxygen, by action of light, is disassociated from the metal and re-
assumes the gaseous state.” Observing that when heating darkened
silver chloride only muriatic acid vapors were liberated, but no chlo-
rine, he concluded “that light produced merely a separation of that
part of the muriatic acid which is tied up in the muriate of silver and
that heat alone seemed to achieve the same result.” He asserted that
silver chloride would blacken as well in the dark from a draught of
air as it does in the light, but this was an erroneous observation. 8

At the beginning of the nineteenth century the considerably widened
knowledge of chemistry and optics and, specifically, the opposed
hypotheses on the nature of light attracted the attention of the learned
world to this subject. There existed for some time the antagonistic
hypothesis of Newton, who describes light as a material emanation
of luminous particles, and that of Euler, according to whom light
originates from the oscillations of the ether produced by luminous
bodies. The founder of the new school of chemistry, Lavoisier, as-
sumed that there existed in nature a particular substance which was the
generating cause of the phenomenon denoted by the name of “light.”
Lavoisier supposed that this light substance was subject to chemical
affinities and therefore combined with other substances or separated
from them and produced noticeable modifications.

In general Berthollet asserted that light became apparent only in
so far as it entered into a compound, that it yielded the quantity of heat
substance which was lacking in the developed gas, and that it increased
its expansibility by a rise in temperature. From these statements it
seemed to him that the identity of the substance of light with that of
heat is proven.

At this time (1802) Thomas Young, 4 the celebrated English phy-
sicist and mathematician, published his discovery of the law of the
interference of light, which, though at first unfavorably received,
finally established the now generally accepted undulatory theory of
light, as stated by the Jesuit Francesco Mario Grimaldi (Bologna,
1665), Christian Huygens (1690), and Leonhard Euler (1746), as
against the molecular theory proposed by Newton, according to which
light was thought to consist of concrete particles emitted by luminous
bodies. 6 Young found that even the invisible ultraviolet rays showed
interference phenomena. In his Experiments and Calculations Rela-
tive to Physical Optics (1804)° he wrote:

Experiment 6.— The existence of solar rays accompanying light, more re-
frangible than the violet rays, and cognizable by their chemical effects,

FROM SAGE TO GAY-LUSSAC

was first ascertained by Mr. Ritter; but Dr. Wollaston made the same ex-
periments a very short time afterwards, without having been informed
of what had been done on the Continent. These rays appear to extend
beyond the violet rays of the prismatic spectrum through a space nearly
equal to that occupied by the violet. In order to complete the comparison
of their properties with those of visible light, I was desirous of examining the
effect of their reflection from a thin plate of air, capable of producing the
well-known ring of colors. For this purpose I formed an image of the rings,
by means of the solar microscope with the apparatus which I have described
in the Journal of the Royal Institution, and I threw this image on paper
dipped in a solution of nitrate of silver, placed at a distance of nine inches
from the microscope. In the course of an hour portions of the three dark
rings were very distinctly visible, much smaller than the brightest rings
of the colored image, and coinciding very nearly in their dimensions, with
the rings of violet light that appeared upon the interposition of violet
glass .... The experiment ... is sufficient to complete the analogy of
the invisible with the visible rays, and to show that they are equally sub-
ject to the general law (i.e., that fringes of color are produced by the in-
terference of two portions of light) which is the principal subject of this
paper.

PRIZE COMPETITION BY THE ACADEMY OF SCIENCES AT ST. PETERSBURG

FOR INVESTIGATION OF THE NATURE OF LIGHT ( 1804) AND THE AWARD

TO LINK AND HEINRICH (1808)

In order to clarify the different views on light the Imperial Academy
of Sciences of St. Petersburg announced (August 22, 1804) a prize of
500 rubles, to be awarded to the scientist who presented to the academy
by 1806 the best dissertation on “the most instructive series of new
experiments on light as matter; on the properties properly attributable
to this substance; its relationship to other organic or inorganic bodies,
and the modifications and phenomena which result in such bodies due
to their combination with the light substance.”

The prize was awarded to two German scientists: Heinrich Fried-
rich Link (1767-1854), professor of natural sciences, botany, and
chemistry at Rostock, director of the University Botanical Garden
and member of the Academy of Sciences at Berlin. The second prize
winner was Placidus Heinrich (1758-1825), Benedictine monk in the
seminary of St. Emmeran at Regensburg; professor of philosophy,
natural sciences, and physics at Regensburg, where he was later made
a member of the chapter of the cathedral.

The essays of Link and Heinrich appeared simultaneously in one
volume bearing the title, Vber die Natur des Lichtes (St. Petersburg,

146 FROM SAGE TO GAY-LUSSAC

1808). Both essays particularize their treatment of the chemical side of
light action and are therefore of great importance to photochemistry.

Link repeated many of the earlier experiments on the light sensi-
tivity of silver compounds and found also new facts— for instance, that
silver chloride darkens more slowly in light under concentrated
sulphuric acid or in strong alcohol than under water and that even at
a temperature of — 50° the blackening does not cease. He studied the
sensitivity to light of silver carbonate, which Buchholz had discovered
in 1800 and which is deoxidized equally by heat and light. He con-
firmed the phenomenon, observed by Sage in 1803 (Scherer’s Journal,
X, 1 15), that sulphide of arsenic bleaches in light; as well as Desmor-
tiers’s statement, 1801, on the supposed light sensitivity of Prussian
blue, and he found that zinc oxide darkens in light.

Without communicating any essentially new observations, Link
cleverly assembled the available experimental material and found that
light deoxidizes many bodies (silver, mercury, and gold compounds) ,
but oxidizes others (guaiacum lac, Dippel’s animal oil, chlorophyll).
He states that “light which combines with the substance during the
photochemical action” (“das verbundene Licht”) cannot be recog-
nized through chemical phenomena; that the wave theory is in no
manner contradicted by chemical experiments, but, on the other hand,
this theory cannot be proven by chemistry.

Concerning the action of light on organic matter Link tells us no
more than Ebermaier had published in 1799 in his Versuch einer
Geschicbte des Lichtes. Referring to the chemical effect of colored
light, Link starts from the works of Herschel and Ritter, previously
mentioned, the first of whom identified many heat rays at the red
end of the prismatic spectrum, whereas the latter discovered invisible
chemical rays (ultraviolet) beyond the violet end. Link expresses the
opinion that the blue and violet rays, as such, act more strongly, and
perhaps not because they contain special chemically actinic rays of
a different nature. He concludes from the fact that silver carbonate
darkens under red glass more quickly than behind blue glass that in
this case the “heat rays” effect the decomposition more thoroughly.
He states verbatim: “The expression ‘chemical rays’ therefore is not
quite logical in its appellation to the rays adjacent to the violet, since
those rays lying beyond the red act likewise and in a perfectly anal-
ogous manner.” Link formulates precisely, although supported by
wholly inadequate experiments, an important law of photochemistry

FROM SAGE TO GAY-LUSSAC

with remarkably keen vision. This law has been substantiated only
in the most modern times through numerous experiments, since up
to the middle of the nineteenth century the erroneous opinion pre-
vailed that chemical action could be attributed only to the blue, violet,
and ultraviolet rays.

Heinrich’s discussion of the action of light is based on the body and
the spirit of man and on plants, and he treats later the chemical effects
of light in a manner similar to that of Link. He also attributes to light
the property of oxidation and deoxidation, but arrives at the untenable
statement that “when light combines with a substance, the acid prin-
ciple is liberated.” That acids are liberated in the photochemical pro-
cesses (for instance, in chloride of silver in the presence of water, etc.)
is quite correct; but Link was careful not to generalize from isolated
cases, a mistake for which Heinrich became a victim.

Especially remarkable also seems the statement of Heinrich on the
light-sensitivity of potassium ferrocyanide, or yellow prussiate of
potash, which decomposes in sunlight, giving off hydrocyanic acid as
gas, and precipitating “Berlin blue.” Later this statement of Heinrich,
as well as still earlier statements by Scopoli and by Berthollet, was lost
sight of, and similar observations were published as new, without re-
specting Heinrich’s priority. 7

Even though, undeservedly, the work of Link and Heinrich is
today 8 entirely neglected, and although the results did not justify the
expectations awakened by the prize essays, we must not underestimate
the influence of these dissertations upon subsequent photochemical
research. For in them there was gathered for the first time all the
available experimental data on the subject, in a manner fairly ex-
haustive and easily comprehensible.

GEHLEN STUDIES THE SENSITIVITY TO LIGHT OF METAL CHLORIDES

In the meantime the experiments on photochemical reactions were
continued on many sides. Campeel showed in 1 804 that light is not as
necessary for crystallization as many believed, since the best crystal-
lization of Glauber salts was achieved on darkest nights. 0

We are indebted to the pharmacist and chemist Adolph Ferdinand
Gehlen (1775-1815) 10 for thorough investigations on the decomposi-
tion by light of metal chlorides in alcohol and ether solutions. He
summed up the results of his experiments (1804) on the action of
light as follows:

148 FROM SAGE TO GAY-LUSSAC

1. A solution of sublimed chloride of iron in a mixture of alcohol
and ether in light forms a colorless ferrous chloride and ethyl chloride.

2. A solution of anhydrous uranium chloride in absolute alcohol
forms a beautiful “lemon yellow solution,” which “when exposed to
sunlight changes within a few seconds; it turns greenish and turbid
and precipitates a muddy green sediment (soluble in water) on con-
tinued exposure.” The ether is discolored and gives an acid reaction
with only a trace of metal. Gehlen concluded that “here, then, reduced
muriate of uranium is formed, which proves insoluble in ether; on heat-
ing with nitric acid it regains its yellow color under development of
nitric acid fumes.”

3. The solution of cobaltous chloride in ether is stable in light.

4. Cupric chloride dissolves in ether and forms a light yellowish
green liquid. The solution bleaches very readily and passes through
brownish yellow to yellow and finally arrives at a completely color-
less state. The solution gives a white precipitate in water. He recog-
nized this substance as “muriate of copper of a minimum of oxidation,”
namely, a reduction phenomenon of cupric chloride to cuprous chlo-
ride.

5. Anhydrous platinum chloride dissolves in a mixture of ether and
alcohol and turns lighter in sunlight. The glass becomes coated under
the action of light on the side directly exposed to the rays of the sun,
with an extremely thin layer of the reduced metal in the form of bright
metallic platinum which consisted of microscopic reguli of platinum.
In the end the original dark brown-red liquid turns to a straw-yellow;
that is as far as the color change went. A solution in ether alone acted
similarly. The solution decomposed by light contained platinous chlo-
ride, as Gehlen quite correctly assumed.

Gehlen concluded:

From the foregoing it follows that all color changes of metal salts solutions
in ether depend upon deoxidation by sunlight. The question therefore
arises, what becomes of the oxygen which is liberated by the oxide? Ac-
cording to my observation the oxygen throws itself upon the ether (com-
bines readily) and brings about a change in it. The latter takes on the odor
of nitric acid .... I thought at first that in the process of bleaching
carbonic acid gas would form, but I could not substantiate this assumption.

We must stress the fact that Gehlen was the first to make known the
light-sensitivity of the compounds of uranium, copper, and platinum.

FROM SAGE TO GAY-LUSSAC

149

In 1805 Theodorus von Swindem published a lengthly dissertation
On the Atmosphere and Its Influence on Colors , 11 in which are to be
found the following statements regarding the action of light on colors:

1. The yellowish green solution of indigo-white from indigo pigment
turns blue in the air, but upon exclusion of air (in a completely filled bottle)
does not undergo any change in sunlight.

2. The green tincture which is obtained by extraction of spinach leaves
in alcohol does not change color in wholly filled and sealed bottles, even
after six weeks’ exposure. In bottles filled only partially, the green color
changes in greater proportion, as air is contained in proportion to the
liquid.

3. Dippel’s animal oil turned black only in sunlight when air was present,
but when the air was excluded or in a nitrogen atmosphere it showed no
change in light, even after fourteen days.

4. White wine did not change color in light, in the presence either of
oxygen or of nitrogen.

5. Decoctions of the bark of holly and of Peruvian bark undergo a
greater change of color in the presence of oxygen than in that of nitrogen,
and this change was still more pronounced when the bottles were exposed
to light.

6. Berberry wood ( Berberis vulgaris), when exposed to light in an
oxygen atmosphere, showed a far greater change in color than under
similar conditions in an atmosphere of nitrogen (agreeing with Senebier).

7. In the process of bleaching linen, the effect of oxygen is greatly
intensified by sunlight. Every expert knows that linen bleaches more
thoroughly and quickly, the stronger the light acts on it; even moonlight
is effective.

8. A mixture of ferrocyanide and iron vitriol, to which is added chlo-
rine water, turns at once a beautiful blue. When the liquid is exposed in
half -filled bottles, a blackish green sediment forms; in fully filled bottles
the usual beautiful blue sediment is precipitated.

9. Ammonia dissolves metallic copper in the presence of air, taking on
a blue color. This reaction occurs much faster in sunlight than in the dark.

Additional and very interesting statements on the behavior of iron
chloride solutions in ether were made by Christian Heinrich Pfaff,

1 805. 12

RITTER ACHROMATIZES THE CHEMICAL AND OPTICAL RAYS (1805)

The observation that by combining certain kinds of glass the re-
fracted “chemical” and “optical” rays may be made to coincide was
recognized by the German physicist Johann Wilhelm Ritter, who

FROM SAGE TO GAY-LUSSAC

150

lived at that time in Munich, where he was a member of the Bayerische
Akademie der Wissenschaften. Ritter was in communication with
other scientists and corresponded also with Jean Baptiste van Mons
(1765-1842 ), who was at that time professor of chemistry and physics
in Brussels, later at the university at Leyden, and was considered one
of the foremost chemists of his time in Belgium.

In September, 1805, Ritter wrote to Van Mons: 13 “I have found,
when using achromatic prisms, that the chemical rays of light follow
precisely the same laws of diffraction and dispersion as those rays of
which the largest part appears luminous to us . .

There is no doubt that this discovery led, after more than thirty
years, to the construction of photographic lenses in which the optical
and chemical foci coincide.

In 1 808 Ritter entered into a controversy with Professor Christian
Ernst Wiinsch of Frankfurt am Main, 14 who disputed the separation
of light in the rays of the sun from heat (1807) in a short article:
“Remarks on Wlinsch’s Dissertation on Herschel’s Experiments with
the Separation of Light Rays.” Ritter states that it was known that
thoroughly dry cerargyrite (hornsilver) does not change color (??)
either in violet or white light or i n the heat from a stove (Scheele) . On
the contrary, moist cerargyrite or that kept under water blackens
early. He also states that in winter the reduction, everything else being
equal, proceeds faster than in summer ( ? ) . At that time he had not con-
sidered the very probable influence of different times of day, although
these undoubtedly could be expected to cause differences. 15 Further-
more, it would be of interest to compare experiments made on days as
bright as possible, simultaneously and under equal conditions, on the
action of light on cerargyrite and other light-sensitive substances, at
great altitudes and at great depths. The results would no doubt differ
greatly from those obtained at the same level under an air pump pro-
ducing compressed and rarificd air. 10 Otherwise the necessity for the
presence of air in the darkening of cerargyrite in light is of the same
value, since it is required for the operation of a galvanic circuit; at least
that was Ritter’s view at that time. The chemical action of light is then
reduced to nothing but a decomposition of water by electricity. Just
as a proportionately strong electrical current can decompose water
independently of the presence of air, so also primarily a light intensified
by condensing lenses can blacken cerargyrite in the absence of all free
oxygen.

FROM SAGE TO GAY-LUSSAC

151

When Ritter leaves the domain of experimental research and invades
the territory of speculation, he is not rewarded by good fortune.
Hasty and ill-founded electrical hypotheses led him astray. It must be
stressed, however, that Ritter, in his observations, had a distinct notion
in his mind of the influence of great height on the power of the chemi-
cal action of light, namely, the law of absorption of chemical light
rays, which Robert W. Bunsen later observed and investigated.

FURTHER ADVANCES IN PHOTOCHEMISTRY

On the action of light on fresh lard Henri August Vogel first pub-
lished in 1806 some statements in his “Dissertation on Lard and Some
Medicinal Preparations Which Are Produced from It.” 17 He states:

It is known that fresh lard properly cleansed has no odor and an insipid,
mild taste. When it is exposed to sunlight for two months, it takes on a
rancid, penetrating odor and a pungent taste which irritates the throat for
a long time; it changes its color from white to yellow, without taking up
any acid. Exposed to sunlight and the action of air simultaneously, the
same phenomenon occurs, but in that case the fat also turns acid.

We find an article in Hermbstadt’s Bulletin des Neuesten und Wis-
senswilrdigsten aus der Natur'ivissenschaft (1809, II, 130) on the
bleaching of bones and ivory which is of interest to us. It is stated here
that animal bones and ivory, when stored for a time in the open air and
in dark places, turn yellowish and even brown, but that they become
gradually bleached in the sunlight. It is therefore recommended to
bleach ivory, etc., in weak caustic potash solution, then in chlorine, and
to expose it to sunlight in order to complete the bleaching process. The
action of the light, it is claimed, operates “by liberating the oxygen
which creates the yellow color.”

DISCOVERY OF THE SENSITIVITY TO LIGHT OF CHLORINE AND HYDROGEN

(chlorine detonating gas) and related light reactions

The combination of the hydrogen-chlorine mixture had been dis-
covered in 1801 by W. Cruickshank, but he did not investigate the
problem very thoroughly. In 1809 appeared an important publication
in photochemistry, namely, a description of the reaction to light of the
mixture of chlorine gas and hydrogen gas. We are indebted for this ex-
periment to the celebrated French chemists Joseph Louis Gay-Lussac
(1718-1850) and Louis Jacques Thenard (1777-1857), a pupil of
Vauquelin, who were the first to conduct investigations on the advance

FROM SAGE TO GAY-LUSSAC

152

of the chemical reaction by light of chlorine gas on hydrogen gas and
on ethylene (oil-fonning gas), which led to many experiments on
similar reactions between chlorine and organic substances. These ex-
periments furnished the starting point for the construction of the
chlorine detonating gas photometer of Bunsen.

Gay-Lussac and Thenard published on February 27, 1809, their
dissertation: “De la nature et des proprietes de l’acide muriatique et
de l’acide muriatique oxigene,” in Mem. de phys. et de chimie de la
Societe d’Arcueil, 1809, II, 339; Gilbert’s Annal. (1810, XXXV, 8).
They also repeated Berthollet’s experiments on the light sensitivity
of chlorine water. A. Fr. de Fourcroy (1755-1809) demonstrated that
chlorine gas was not decomposed by light or heat. Gay-Lussac and
Thenard state:

We have, then, discovered a substance which is not decomposed by light
or heat, but by addition of water is easily disintegrated by either, namely,
as steam under mild red-heat .... When the actions of light are com-
pared with those of heat, it must be conceded that in general both produce
the same effect. This conclusion had been already arrived at by Rumford.
. . . We made two mixtures, each of which consisted of equal amounts
of oxygenated hydrochloric acid gas (chlorine) and hydrogen gas ....
One was put in a completely dark place, the other in sunlight which was
rather weak on that particular day. After a few days the color of the
former was still green and the mixture did not seem to have undergone
any change. The latter, on the contrary, was completely discolored in less
than a quarter of an hour and was almost completely decomposed ....
We made further mixtures of oxygenated hydrochloric acid gas, partly
with hydrogen and partly with ethylene gas . . . and exposed both mix-
tures to the sun; this was hardly accomplished when they suddenly ignited
with an extremely loud detonation and broke the bottles into pieces which
were strewn all over the place. Fortunately, we were rather dubious about
these experiments, and we had taken precautions against accidents . . . .
Carbon oxide has no reaction on chlorine (?).... Light seems to act
on dyestuffs in the same manner as heat of 150-200 degrees .... It is
possible that light acts on plants only as heat does, but with the important
difference that heat increases the temperature, but light, on the contrary,
produces an inequality of temperature (just as in chlorine water), because
it affects some parts sooner than others, which seems to be of great advan-
tage to the scope and play of the organic forces.

Joseph Louis Gay-Lussac (1778-1850) was an eminent French
physicist and chemist. He lectured as professor of physics at the Sor-

FROM SEEBECK TO DAGUERRE

i53

bonne and as professor of chemistry at the polytechnic school. He was
a member of the Chamber of Deputies from 1830 and was elected to
the House of Peers in 1839. We owe to him a lengthy series of impor-
tant discoveries in physics and chemistry, which space does not permit
us to consider here. We must, however, record those discoveries which
are connected with photochemistry and photography, especially his
works on detonating chlorine gas, iodine, and iodide of silver (1814).
Alkalimetry, acidimetry, and chlorometry are his inventions, and his
instruction on the volumetric examination of silver was used not only
in mints and analytical laboratories but also later in photography. Much
of his scientific work was carried on with Thenard, who was associated
with Gay-Lussac and others on the commission appointed to study
the value of Daguerre’s invention. Gay-Lussac made a report on this
subject to the Chamber of Peers in 1839, recorded in our chapter on
daguerreotype.

Chapter XVII. from the discovery of

PHOTOGRAPHY IN NATURAL COLORS BY SEEBECK
(1810) TO THE PUBLICATION OF DAGUERRE’S PRO-
CESS (1839)

The discovery of photography in natural colors on silver chloride
was made by the famous German physicist Johann Thomas Seebeck
during his experiments with the solar spectrum. He was induced to do
this work by Goethe, who lived in Weimar while writing his Geschi-
cbte der Farbenlehre and was on friendly terms with many scholars,
among whom was Seebeck. He was born in Reval, Estonia, studied
medicine at Berlin and Gottingen, and lived in Jena from 1 802 to
1810 as a well-to-do scholar. 1 He spent his time with chemistry and
optics and discovered thermoelectricity; he was elected a member of
the Academy of Sciences at Berlin, where he died in 1831.

Goethe, during his studies on the science of color, devoted special
attention to Newton’s theory of the solar spectrum. He delved deeply
into the historical side of the science of color, from the ancient Greeks
to modern times, and endeavored to support his teachings about color
by means of new optical experiments. This brought him into contact

1 54 FROM SEEBECK TO DAGUERRE

with Seebeck, who lived not far away, in Jena. Seebeck investigated
the chemical action of the solar spectrum, and these studies resulted
in his sending a dissertation, Wirkung farbiger Beleuchtung, to Goethe,
who added it to the appendix of his Geschichte der Farbenlehre, which
was published in 1810.

Seebeck described therein the action of the solar spectrum on lumin-
ous minerals, and on that phenomenon is built a further dissertation
by Seebeck of great importance in the history of photography: Von
der chemischen Aktion des Lichtes und der farbigen Beleuchtung.

Seebeck writes 2

that when he projected a solar spectrum upon paper prepared with still
moist white homsilver 3 and the light action was allowed to continue for
a quarter of an hour or a little longer, the following results were observed:
in the violet band of the spectrum the chloride became reddish-brown,
sometimes tending to violet. This coloring extends all through and a little
beyond the violet. In the blue part of the spectrum the chloride of silver
becomes clear blue; the tint becoming fainter in the green. In the yellow
no action took place, or only a faint yellow tint was produced; but in the
red and ultra-red a rose or lilac coloration resulted. In the case of some
prisms this reddening fell entirely outside the red zone of the spectrum
.... When homsilver, which had turned gray in light and is still moist,
is exposed for the same length of time to the prismatic spectrum, it changes
in the blue and violet, as above; in the red and yellow, however, the silver
chloride will be found lighter in color than before, that is, perhaps not
just lighter, but sharper and unmistakably more distinct. A reddening in
or immediately below the prismatic red will also be observed .... Silver
chloride turned gray under violet, blue, and blue-green glass, just as in
sunlight or daylight, exhibited different characteristics according to the
varieties of glass . . .

Thus, we note that apart from Senebier, who made far less detailed
statements on the photochromy of silver chloride, Seebeck was the first
who discovered that chloride of silver was capable of absorbing all
natural colors of the solar spectrum and of colored glass; he recognized
the property of silver chloride, which had turned gray under light
(the so-called “silver subchloride”), becoming lighter (yellowish)
in yellow light and reproducing also all other colors. That he also
observed color sensitivity in the presence of “white silver chloride”
can probably be traced to the fact that his spectrum was mixed with
diffused white light, so that silver subchloride could form, which re-
produces the colors; pure white chloride of silver in a pure spectrum

FROM SEEBECK TO DAGUERRE

1 55

turns dark only in the more refrangible end, without reproducing the
action of the colors. This was not observed by the earlier physicists,
including Scheele and others, in similar experiments, nor did C. H.
Pfaff later succeed in it. Seebeck also discovered the chemical action
of infrared rays, which gave him enduring fame, although his contem-
poraries paid very little attention to his discovery.

In 1819 he called attention in great detail to the fact that the spec-
trum produced by various kinds of glass differed with regard not only
to the action of heat but also to chemical action on silver chloride, which
could be traced to the varying light-absorption ability of crown and
flint glasses in the violet and ultraviolet spectrum. 4

Seebeck made numerous other experiments in the interest of
Goethe’s studies on color. 6 W e shall mention here only his observation,
also contained in Goethe’s work, that red oxide of mercury under blue
glass is reduced in sunlight (changes into gray, imperfect oxide), but
does not so react behind yellow glass, and that nitric acid and Bestu-
scheff’s nerve tincture behave in an analogous manner under colored
glass. In the following year ( 1 8 1 1 ) Seebeck connected his experiments
with those of Thenard and Gay-Lussac on chlorine-hydrogen gas, 8
and states: “I filled a yellow-red and a dark blue glass bell with these
kinds of gas (Cl + H) and exposed them to sunlight. In the dark blue
bell decomposition set in at once, but without an explosion, and it was
quite finished in less than a minute .... In the yellow-red vessel the
decomposition proceeded very slowly.”

Seebeck was also the first to observe, in 1812, that the flame from
Bengal lights caused an explosive combination of chlorine and hydro-
gen and caused a detonation. 7

In 1813 a polemical pamphlet was published by C. H. Pfaff, pro-
fessor at Kiel, on Newton's Farbentheorie, Herr von Goethe's Farben-
lehre und der chemische Gegensatz der Farben, Leipzig, in which the
author quite properly remarks that he cannot comprehend how See-
beck, after discovering that silver chloride assumes different colors
in the spectrum, could be satisfied with the mere accidental colors
(according to Goethe) of the color science. Pfaff remarks that he
was unable to attain the natural colors of the spectrum on silver chlo-
ride, but he never doubted the correctness of Seebeck’s observations.
He also made experiments with sulphate of mercury, tincture of litmus,
and so forth, and found: “In most cases it seems that violet and blue
light have a deoxidizing effect, while red light mostly effects oxidation

1 5 6 FROM SEEBECK TO DAGUERRE

(silver chloride, sulphate or mercury, litmus, Bestuscheff’s tincture);
on the contrary, however, the violet rays caused oxidation on guaiacum
tincture and phosphorus.”

FURTHER PROGRESS IN PHOTOCHEMISTRY

Gay-Lussac and Thenard collected their observations as early as
1 8 1 1 in their Recberches physico-chimique (i8ii, II, 186), on the
comparative effects of light and heat during chemical processes, stat-
ing their conclusion in the following statements: 8

1. Gold and silver solutions brought into contact with oils, ether, and
carbon are decomposed by light; this occurs also by heat of ioo° C., as
Rumford demonstrated.

2. The dry oxidized hydrochloric acid gas (chlorine) is not decom-
posed by the strongest light or by greatest heat.

3. Aqueous oxidized hydrochloric acid (chlorine water) is decomposed
by comparatively weak light, as well as by heat at dark-red heat.

4. Concentrated nitric acid is decomposed by very intense light, also
by red heat.

5. Oxidized hydrochloric acid gas with hydrogen gas or hydrogenated
carbon oxide gas 9 detonates when the sun’s rays touch it; it is also de-
tonated by heat 1 25-160° C.

6. Oxidized hydrochloric acid gas mixed with hydrogen gas is decom-
posed only slowly by diffused light. These two kinds of gas affect each
other only slowly or not at all under 120° C.

7. Black mercury oxide changes in light into mercury and red mercury
oxide; this change is due to heat.

8. Brown oxide of lead and no doubt also the oxides of silver, gold, and
platinum decompose in light as well as in heat.

9. The rose color of safflower is decomposed by light and becomes dirty
white; this same change takes place in heat of 1 60° C. in one hour.

10. The violet color of logwood (campeche) is decomposed by light
and becomes reddish yellow and dull; in one and a half hours at 180° C. of
heat it also turned reddish yellow and dull.

1 1. Light decomposed the red color of brazilwood and turned it almost
white; heat did the same in two hours under 190° C.

12. The orange color of curcumine is decomposed by light and turns
a rust color; a rusty color also appears in one and a half hours under 200° C.
of heat.

13. Finally, the yellow color of woad became ochre in light; the same
change took place in two and a half hours at 210° C. heat.

FROM SEEBECK TO DAGUERRE

i57

In conclusion Gay-Lussac and Thenard made the assertion that
light produced no chemical action which was not generated by more
or less heat.

This statement afterward started a series of lively controversies
which showed that their views were correct in many, but not all, cases,
which was also demonstrated by Davy in the following year.

The opinion previously expressed by Link and Heinrich that light
acts by sometimes oxidizing, sometimes reducing was confirmed by
Wollaston ( 1 8 1 1 ) in experiments with guaiacum and paper coated
with an alcoholic tincture of guaiacum. An interesting account of these
experiments is to be found in the 1831 edition of Brewster’s Optics
(p. 91). Wollaston concentrated the various spectral rays on the card
prepared with guaiacum by means of a lens. In the violet and blue rays
it acquired a green color; in the yellow no effect was observed. Pieces
of the prepared card which had become green in the violet or blue
rays were restored to their original tint by exposure to the red rays.
In an atmosphere of carbonic acid the violet and blue rays did not make
the prepared card green; but the restoration of the original tint by the
red rays took place in an atmosphere of carbonic acid. Heat also was
found to destroy the green color. 10 He therefore termed the refrangible
rays “chemically active rays” and opposed the term “reducing rays,”
which Ritter at that time used.

Ruhland also states in his “Fragmente zu einer Theorie der Oxy-
dation” 11 that it had been found that sunlight accelerates the weathering
of crystals containing water of crystallization and that light often
oxidizes: “Thus oxidation in the galvanic pile, according to Buchholz
(and with it, its efficiency) is increased by light, and thus iron oxidizes
more rapidly in light than in the dark.”

In 18 1 1 the development of the wave theory of light was renewed
by Thomas Young, 12 which was of great importance for mathematical
optics, but caused no advances in photochemistry.

A new genius, Fresnel, appeared in the field of science in 1815 and,
supported by Arago, won after a hard fight the splendid victory of
establishing the wave theory over the theory of emission. 13 This effec-
tually banished the earlier view that “a part of the light substance”
(ein Teil des Lichtstoffes) combines with chemical substances. Ac-
cording to the Fresnel- Arago view it was distinctly expressed that in
the chemical action of light on silver salts, and so forth, no combina-
tion takes place between “light particles” ( Teile des Lichtes ) with

FROM SEEBECK TO DAGUERRE

158

those of the substances on which it acts. The decision in this case,
therefore, was not established by chemical experiments, but as a con-
sequence of the wave theory of light substantiated by mathematical-
physical methods.

The general consideration of the nature of the chemical processes
which cause the more refrangible rays of the solar spectrum, and also
the less refrangible rays, was continued on many sides. Davy published
in 1812 his Elements of Chemical Philosophy . He opposed the theory
of Gay-Lussac and Thenard that the chemical action of light was
similar to that of heat; he points out:

“Of the effects of radiant matter in producing chemical changes. Fourth
observation: I have found that a mixture of chlorine and hydrogen acted
more rapidly upon each other, combining without explosion, when ex-
posed to the red rays than when placed in the violet rays .... I have
found that the black oxide of mercury exposed in red rays concentrated
by a lens gradually became red; in which case oxygen was probably ab-
sorbed; but the same oxide, exposed in the violet rays concentrated in the
same manner was not changed; and these rays produced no effect upon
dry red oxide of mercury, but upon moistened red oxide occasioned the
same effect as a current of hydrogen gas .... The facts that 1 have
stated above sufficiently demonstrate that the rays producing heat are
capable of assisting certain species of chemical action, and there seems no
more reason for asserting that the rays producing no heat are the rays
most efficacious in occasioning chemical changes than for asserting, with
MM. Gay-Lussac and Thenard, that light produces all its chemical effects
by producing heat .... And from the observations of M. Berthollet, it
appears that muriatic acid gas is formed when hornsilver is blackened by
light, so that they may be called hydrogenating rays . . . £pp. 155, 211,
etc.]

Davy also endorsed the opinion, which was later often stressed, that
refrangible rays reduced (hydrogenated), while the less refrangible
ones oxidized, which view, according to the state of photochemical
knowledge of the times, was not wholly unreasonable, but was opposed
by Wollaston and others. In modern times it has been contradicted by
new experiments.

In 1812 Davy also found that carbonic oxide and chlorine gas com-
bine in sunlight. 14 A. Vogel, in Paris, thoroughly investigated the be-
havior of phosphorus (see Bockmann, ch.xv,note 9) and its compounds
toward light; Bockmann discovered the sensitivity to light of phosphor-
eted hydrogen 16 and later studied the action of sunlight on phos-

FROM SEEBECK TO DAGUERRE

i59

phorus. 18 He observed that it changes phosphorus to red, even under
water, in a vacuum as well as in an atmosphere of nitrogen and hydro-
gen, wherein the violet rays of the spectrum acted more rapidly than
the red. 17 Ruhland’s observations are similar, as may be seen in a dis-
sertation Vber den Einfluss des Lichtes auf die Erde, which he sub-
mitted in 1813 to the Akademie der Wissenschaften of Munich. 18

Vogel made further experiments with a watery blue infusion of
violets, to which a little alcohol was added, which loses its color rapidly
in blue light, slowly in red light, which is also the case of a poppy in-
fusion. He also found 19 that “copper oxide-sodium oxalate has the
peculiar property of turning in sunlight very rapidly and in the shade
gradually, green, then dark brown, without losing any weight, shape,
and as it appears, none of its luster.”

Ruhland described further experiments of Vogel in Schweigger’s
Journal 20 (1813, IX, 236). Vogel found:

1. Fresh crystals of sodium phosphate, sodium sulphate (Glauber’s salt),
iron sulphate effloresce more rapidly under blue than under red glass.

2. Phosphorus in “pure nitrous gas” (nitrous acid?) is stable in light.

3. An alcoholic tincture of red carnations turned white in a few days
behind blue glass, while behind red glass it was still purple after about the
same length of time. Cotton and paper colored with this tincture showed the
same differences. The petals of a corn poppy (papaver rhoeas), mounted
behind a blue glass, turned whitish after a few days; behind a red glass the
color remained unchanged. 21 The fatty oils turned gradually acid in light.

4. Phosphorus and caustic potash exposed under blue glass developed
considerable gas and dissolved; behind red glass the same action took place,
but much weaker and more slowly.

5. A solution of iron chloride in ether loses its golden yellow color in
a few minutes behind blue glass, while behind red glass it remains unchanged
for a whole day. Since this solution is extremely light-sensitive, “It may
some day become a good measure for the intensity of light.”

6. A solution of copper chloride presents the same phenomenon behind
colored glass.

7. A saturated solution of mercuric chloride in ether shows no change
in light behind red glass; behind blue and clear glass a mass of small crystals
formed. The precipitate turned black in caustic potash, “which proves that
the precipitate was mercurous chloride (calomel).” A solution in pure
alcohol behaves similarly, but decomposes more slowly.

8. Ammonium sulphide exposed to light in blue and red glass bottles
undergoes a change only in the blue containers; after two months the sides
are coated with a crust.

160 FROM SEEBECK TO DAGUERRE

It is worth mentioning that the chemist Doebereiner, of whom we
shall speak later, found in 1813 that alkaline hypochlorite (Javel solu-
tion) and chloride of lime (bleaching powder) change more rapidly
in the light than in the dark. (Schweigger’s Jour., 1813, IX, 18).

FISCHER DISCOVERS THE LIGHT SENSITIVITY OF SILVER ALBUMINATE
AND CONTINUES THE STUDY OF SILVER CHLORIDE ( I 8 I 2 )

The sensitivity to light of silver albuminate, which is important in
the production of albumenized photographic paper, is mentioned for
the first time in 1 8 1 2 in an article “Kritik der von dem Herrn Professor
David Hieron Grindel fortgesetzten Versuche fiber die kiinstliche
Bluterzeugung,” by N. W. Fischer. 22 He was the first to call attention
to the light-sensitivity of silver albuminate, so important in photog-
raphy as a well-known phenomenon:

When animal fluids, i.e., albumen, are mixed with a silver solution and are
exposed to light, the silver combines in a mild oxidizing, but not definite,
condition with the animal substance and turns black, as is well known;
however, this color is at first brownish-red and changes later, often onlv
after several days, to dark brown or black.

He adds a footnote:

As everyone may observe who stains his hands with a silver solution. But
the silver solution, or at least the acid, must not be too strong, for when
that is the case the stains will soon turn black, although a dirty black.

This shows that Fischer already knew that the blackening process in
photography was influenced by the presence of free nitric acid.

The knowledge of the sensitivity to light of silver compounds was
greatly enlarged by the special study of Fischer published under the
title Vber die WirkungdesLichtesaufHornsilber 23 (Nuremberg, 1814).
This pamphlet contains a valuable historical review, with detailed
descriptions of his own experiments. Since this booklet has become
extremely rare, I record below the most important conclusions:

1. (a) The blackening of muriate of silver is due exclusively to the
action of light. Link stated the same. Scheele, Senebier, Vasalli, Heinrich,
and Buchholz held that heat co-operated. According to Ritter, silver
chloride does not change color at 0° C. Berthollet states that a current of
air causes blackening; but according to Ritter only after it had been heated
by fire and gave out carbon.

(b) Chloride of silver changes color even at 1 6° to 18 0 R. Increase of
heat alone effects no color change, and light does not act on dissolved
silver chloride.

FROM SEEBECK TO DAGUERRE 161

2 . The color of silver chloride proceeds from bluish gray to red brown.
According to the condition, namely, the purity of the compound, a different
kind of color change takes place. In a compound in which there was excess
of muriatic acid and which was dried quickly in large pieces, sunlight
effected no change in color until the preparation was moistened.

3. Water, while facilitating and hastening the color change in silver
chloride, is not absolutely necessary to this phenomenon, because it occurs
in any colorless liquid and in dry air. Fischer demonstrated this with dis-
solved silver chloride, which when exposed by him in sulphuric acid,
nitric acid, alcoholic ether, nut oil, was colored up to red-brown in all
these cases; although most rapidly in water and most slowly in nut oil.
Silver chloride also changed color in air dried over calcium chloride
Scheele found that silver chloride did not change color in nitric acid.
(Fischer remarks that he must have used red nitric acid.)

4. (a) The nature of this phenomenon (color change) is the decom-
position of silver chloride by light, and that one constituent, the oxidized
muriatic acid, is liberated, which escapes in a gaseous state or communicates
itself to the liquid.

(Gilbert was the first to express this view: that chlorine is set free and
forms with the hydrogen of the water, hydrochloric acid; Scheele, Senebier,
Berthollet, Heinrich, Buchholz confirm simply the solution of hydro-
chloric acid.)

Fischer found that silver chloride in light yields chlorine not only to
water but also to alcohol, ether, nitric acid; these liquids then react with
silver nitrate.

During the time that dry silver chloride blackens in sunlight, an odor
of chlorine develops. Silver chloride + water gives off the odor of chlorine
after eight to fourteen days; it bleaches vegetable dyes (litmus, curcuma).
Dry molten silver chloride also generates chlorine gas, although more
slowly. Alcohol gives off the odor of chlorine ether. Therefore it is chlorine
(not muriatic acid) which is set free.

(b) Pure molten silver chloride lost 1/500 in weight after four weeks'
exposure (0.02 g. out of 10 g.).

5. The change which chloride of silver undergoes in the blackening
process is “that it passes from the state of a neutral compound to that of a
basic salt. The portion of silver liberated by the muriatic acid combines
with the undecomposed muriate, forming a salt with excess of the base”
(namely, silver subchloride!!!).

He supported this statement by the following experiments:

(a) Blackened silver chloride is not made lighter by muriatic acid or
sulphuric acid, which shows that no silver oxide could have been liberated
(as Berthollet, Buchholz, Gilbert assumed).

1 62 FROM SEEBECK TO DAGUERRE

(b) If nitric acid is added to completely blackened silver chloride, a
silver solution forms, but only when the muriate (silver chloride) is com-
pletely blackened; particularly when the color change takes place in the
beginning under water was the change not entirely completed; the nitric
acid dissolved no silver. In no case was the silver chloride decolorized, even
if the nitric acid absorbed some silver; in which case, it is true, the color
became somewhat lighter.

(c) The darkened silver chloride is no longer entirely soluble in am-
monia like the uncolored; the residue is silver gray, completely soluble
in nitric acid (as Scheele assumed, contrary to Berthollet’s view). This
does not prove, as Scheele believed, that ammonia simply liberates the
silver formed by light, “but that ammonia itself has a decomposing action
on the muriate and liberates silver.” The product of the color change cannot
be considered as a mere mechanical combination of undecomposed muriate
and free silver, for otherwise the nitric acid would dissolve the free silver
and thereby be able to produce the white color, which does not happen.
The chemical union between the decomposed and undecomposed muriate
is so intimate that nitric acid is not able to separate them.

6. On the difference between the oxidation in the red and the reduction
in the violet, Fischer adopted a doubtful and reserved position.

7 . All kinds of light produce these effects (color change and reduction)
more rapidly in sunlight than in daylight; blue and violet act rapidly, red
less, then comes the light from flames, and last moonlight.

Other works of Fischer which are of interest to us followed in 1 8 1 8,
when he wrote “Ober die Ausscheidung des Silbers aus dem Chlor-
silberdurch Zink” (Schweigger’s Jour., 1 8 1 8, Vol. XX). This method
afterward was often employed for the recovery of silver from silver
waste (also see ibid.., 1826, p. 222).

THE DISCOVERY OF IODINE (1814)

Iodine was discovered in 1814 by Bernhard Courtois (1777-1838)
a manufacturer of saltpeter in Paris. Courtois used for the decomposi-
tion of the calcium nitrate the alkaline lyes of varec or kelp and ob-
served in the process a strong corroding action on the copper vessels.
Careful investigations (1812) led to the determination that the cor-
rosion of the metal was caused by a combination of the copper with a
substance heretofore unknown, but then isolated by Courtois— it was
iodine. Although Courtois received a prize of 6,000 francs for his
discovery from the Academy of Sciences (1831), he died in poverty
and want, having lost all the capital invested in his factory, owing to the

FROM SEEBECK TO DAGUERRE 163

subsequent admission of saltpeter from India free of duty. Courtois
sent samples of the new element to Desormes and Clement for further
study, and they reported in detail on the properties and behavior of
iodine to the Imperial Institute of France, on November 29, 1813. On
December 6, 1813, Gay-Lussac also reported his experiment on “iode,”
as he designated the element, and a short time later Davy, who was
passing through France, received a sample of the element from
Ampere. He was able to support Gay-Lussac’s statements, especially
as to the elementary nature of iodine, so-called by Davy in order to
conform with the endings of chlorine and fluorine 24 (D. Chattaway,
Chem. News, 1909, XCIX, 193-95; Cbemiker-Zeit., 1909, Repert.,
p. 261).

Davy 26 reported to the Royal Society of London, on January 20,
1 8 14, on the different properties of iodine. In this extremely interesting
report of his “Some Experiments and Observations on a New Sub-
stance Which Becomes a Violet Coloured Gas by Heat,” for which
he proposes the name “iodine,” Davy briefly summarizes the earlier
experiments of Gay-Lussac, Desormes, and Clement, and continues:

The first experiments that I made on this substance, were to ascertain
whether (argentane) muriate of silver could be formed from its solution
in water or alcohol, and for this purpose it was purified by distilling it
from lime. Its solution I found, when mixed with solution of nitrate of
silver, deposited a dense precipitate of a pale lemon colour; this precipitate,
when collected and examined, proved to be fusible at a low red heat, and
then became of a red colour. When acted upon by fused hydrate of
potassa, it was rapidly decomposed, and a solid substance, having all the
characters of oxide of silver, was formed. The matter soluble in water
separated by a filter, and acted upon by sulphuric acid, afforded the
peculiar substance.

A solution of potassa, after being boiled on the precipitate, afforded
the peculiar substance, when treated by the same acid.

The precipitate was much more rapidly altered by exposure to light
than the muriate of silver, and was evidently quite a distinct body.

Davy perhaps prepared his iodide of silver with an excess of silver
nitrate, since his preparation changed rapidly in light, which, as is well
known, occurs only in that case.

Worthy of mention also are the investigations of Steffens, Link, and
Fischer, who were first given the opportunity to engage in experiments
with iodine and silver iodide by the courtesy of Gay-Lussac. Henrik

1 64 FROM SEEBECK TO DAGUERRE

Steffens (1773-1845) received his degree as doctor of medicine and
philosophy at Kiel, taught there and at Copenhagen, was professor of
physics at Breslau from 1804 to 1832, and later in Berlin. He occupied
himself with geology, geognosy, anthropology, and physical subjects.
While at Paris, early in 1814, he visited Gay-Lussac, who gave him
a small quantity of iodine, at that time a great rarity. With this he
made experiments, together with H. F. Link and N. W. Fischer, with
iodide of silver. The results, published by all three authors in Schweig-
ger’s Journ. f. Chemie und Physik (1814, XI, 133) did not coincide
with those presented by Davy. The three chemists observed that silver
solutions are precipitated by iodine and that the precipitate greatly
resembles silver chloride, but they stated: “The precipitate (light
greenish-yellow) compound as well as the melted compound (iodide
of silver) retain their color under light.” 26 This observation, contrary
to that noted by Davy is probably explained, by the supposition that
the last-named chemists evidently precipitated the silver iodide with
excess of potassium iodide; it did not occur to the scholars of those
times to observe the different behavior toward light of the melted and
precipitated iodide of silver. The fact that silver iodide turns dark in
light much less rapidly than does silver chloride, diverted the attention
of physicists from the former, and it was considered of little importance
in photochemistry until used by Daguerre. Boullay had discovered
in 1 82 7 the double salt of silver iodide with potassium iodide and had
observed that in light it assumed a pale blue color ( Annal . d. Chemie
u. Physik, XXXVII, 37). However, the photochemical decomposi-
tion of this double salt is very limited.

From then on iodine and iodides were of importance only in medi-
cine, but not in photochemistry. When Dr. Coindet of Geneva recom-
mended, in 1820, that iodine be used as a cure for goiter, it received
wide dissemination and increased considerably in price.

The physicists, on the other hand, occupied themselves in those
days more with silver chloride, which in light turns black more rapidly
than silver iodide.

PROGRESS IN PHOTOCHEMISTRY UNTIL THE DISCOVERY OF BROMINE

Subsequently separate observations accumulated on the light sen-
sitivity of various substances. In his “Experiments on the Reciprocal
Action of some Ammonia Salts and Oxidized Mercuric Chloride
(=HgCl 2 )” L. A. Planche 27 described in 1815 the action of light on

FROM SEEBECK TO DAGUERRE 165

a mixture of ammonium oxalate and mercuric chloride solution. He
mixed equal volumes of a cold saturated aqueous solution of ammonium
oxalate and sublimate, filled with it a small Woulf jar (tube de Welter)
nine-tenth parts, and attached a gas-delivery tube. When he ex-
posed the jar to strong sunlight, the mixture became turbid after
two minutes. Gradually it became milky, and then it deposited a
certain quantity of “mercuric chloride in minimum” (calomel). Now
“the surface of the liquid began to boil,” and by a retarded motion
of it, bubbles of carbonic acid were disengaged. This separation of
gas continued for several hours, and then the liquid became clear.
That these two salts actually decompose under the influence of
light, Planche proved by putting aside in a dark place a sample of the
solution; even after eight days not the slightest change could be noticed.
The access of light, he concluded, seemed necessary to the reciprocal
decomposition of the caustic sublimate and the ammonium oxalate.

Dr. Eder afterward based his photometer with mercury salts on
this reaction.

ON THE LIGHT SENSITIVITY OF MANGANIC SALTS

Friedrich Brandenburg (1781-1837), a German pharmacist and
honorary member of the Imperial Academy of Sciences at St. Peters-
burg, was the first to record the light sensitivity of manganic salts.
Although long domiciled in Russia, most of the results of his investiga-
tions were published in German chemical journals. He reported in
1 8 1 5 28 “that a reddish, clear solution of manganese, prepared with pure
sulphuric acid and containing much free acid, when kept undisturbed,
under exposure to light and in the open air, became at first turbid
but soon after lost its color completely, after one or more days.”

Schweigger adds 29 that he also observed that a beautiful red solution
of sulphate of manganese 30 was discolored only in light and that the
solution which had lost its color did not regain it in the dark. Fromberg,
who investigated manganic acid later (i 824), 31 states that an aqueous
solution of it was light-sensitive, that is, loses color.

The behavior of organic substances toward light also attracted more
attention. J. Pelletier and Cavetou, 32 in 1817, made detailed investiga-
tions of the green coloring matter of plants, the “grime Pflanzenharz”
(green vegetable resin) as extracted by alcohol, ether, and so forth.
The alcoholic solutions of the green substance produced with lime,
alumina, magnesia salts, and so forth, green pigments on which the

1 66 FROM SEEBECK TO DAGUERRE

light manifested in general no deleterious influence; only the green
matter of spruce and pines suffered a change. Johann Andreas Buchner,
in a note commenting on this, states that he also had investigated this
subject several years earlier and had found that the green pigment of
various water plants, extracted in alcohol and laid on paper, linen,
cotton, and silk, faded very quickly in sunlight and changed to a pale
yellow or dirty brown. 33

In 1 8 1 8 Luigi Gasparo Brugnatelli, at the University of Pavia, in-
vestigated purpuric acid formed from uric acid and found that the
colorless crystals containing water turn red in sunlight, also when
heated. When, however, they have lost their entire water content, sun-
light no longer changes their color and heat decomposes them, without
their assuming a red color. 34

GROTTHUSS EXPRESSES THE LAW OF PHOTOCHEMICAL ABSORPTION IN I 8 I 7
AND EXTENDS THE THEORY OF PHOTOCHEMICAL REACTIONS

With the beginning of 1817 we must turn our attention to the
activities of Theod. Freiherr von Grotthuss, born in Leipzig, January
20, 1785, where, as well as in Paris, he received his training in the
natural sciences. In Paris he attended the Polytechnic Institute and
studied under Vauquelin, Berthollet, Fournier, and others. When the
Franco-Russian war began, in 1804, he was forced to leave Paris and
went to Rome and Naples, where he turned his attention to electroly-
sis. In 1805 he proposed a remarkable theory of the galvanic de-
composition of water. In 1 806 he returned to the estate inherited from
his father in Russia. There he engaged in the cultivation of his estate
and continued his scientific works.

Although Grotthuss only reached the age of thirty-seven, his works
are important, particularly in photochemistry. It was he who in 1817
expressed for the first time the opinion “that only the absorbed light
rays are active in the production of chemical changes” (Gilbert’s
Annals, 1817, LXI, 50). Thus, he formulated the important basic law
of photochemistry, which is named after him, “the Grotthuss law of
photochemical absorption.”

The publication of this law received little notice at that time, al-
though there existed some previous works on the subject by Christian
Weiss, in 1801, and by A. Vogel, 1813. This important Grotthussian
thesis was in time so completely forgotten that John William Draper,
two years after the invention of the daguerreotype, discovered the

FROM SEEBECK TO DAGUERRE 167

same law anew and entirely independently of Grotthuss (Phil. Magaz.,
1841, p. 195). Fora long time it was known as “Draper’s law of absorp^-
tion,” in ignorance of Grotthuss’s priority (Eder’s Photochemie, 3d
ed., 1 906, p . 4 1 ) . Draper also recognized that in every chemical change
in a substance caused by light, certain rays of definite wave-length are
absorbed, which absorption produces the photochemical change.

This basic photochemical law, however, originated with Grotthuss;
but he and Johann Heinrich Schulze suffered the same tragedy, that
about a century passed before as pioneers in the field of photochemis-
try they received due recognition.

Not until the end of the nineteenth century was attention again
drawn to the work of Grotthuss and the “Grotthuss law,” universally
accepted under his name. In the twentieth century it was formulated
again and made to conform with modern theories 35 by van’t Hoff,
Plotnikow, and others.

Let us return to Grotthuss’s work of 1 8 1 8 . In that year he found that
sulphocyanide of silver is blackened by light, but less so than silver
chloride. 38 In October of the same year he presented to the Kurland
Society for Literature and Art a dissertation Vber die chemische
Wirksamkeit des Lichtes , 37 in which he set forth photochemical propo-
sitions 38 which were original.

Grotthuss tried to connect photochemical action with galvanic
action, because Davy and Berzelius (1810) had pointed out the con-
nection between chemical and electrical forces. Starting with Ber-
zelius’s electrochemical theory, Grotthuss held that positive electricity
(+E) negative electricity (— E) are the true elements of light, and
expressed the view that light separates the constituent parts of many
combinations and forces them into combinations with electrical matter.

He endeavored to bring together under four laws the photochemical
phenomena known in his time, and made many new experiments for
the demonstration of his theory, which greatly enlarged our know-
ledge on the light sensitivity of chemical substances.

The four laws of Grotthuss are:

1 . In certain solutions, especially those which dissociate, the light
separates the nearest constituent, so that the new compound formed
by the separation shows under the given conditions the greatest possible
difference in solubility. Example: Stannous chloride dissolved in water
and covered with oil is said to turn turbid more rapidly in sunlight
than in the dark, “whereby basic stannous oxychloride separates, while
the acid salt remains in solution.”

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1 68

2. In oxygen and chlorine compounds which are decomposed by
light, the light usually deoxidizes or dechlorizes the ponderable electro-
positive constituent, or prevents its oxidation or chlorination; simul-
taneously it oxidizes or chlorinates the electronegative or other in-
different element. Example: Silver chloride forms in light first free
chlorine; this, by action on water, forms muriatic acid, “since the oxygen
contained in water combines with the +E of light and the silver with
the — E of light,” for instance, loss of color in the tincture of iron.

3. On compounds the constituent parts of which are capable of
hydrogenation or dehydrogenation, the light acts in such a manner
that the electronegative constituent is hydrogenated, while the elec-
tropositive constituent is dehydrogenated, because it transfers at the
same time its imponderable elements (±E) chemically to the newly
formed compounds. Example: Aqueous starch iodide turns colorless
in light, since hydrogen iodide forms. 39

4. When light acts on oxygen and solutions of certain salts which
already have themselves undergone a change by light or have suffered
a similar reaction, the light will deoxidize the imponderable +E of the
oxygen gas and oxidize the next electropositive constituent of the salts,
and so forth. Example: The blood-red solution of iron sulphocyanide
becomes discolored by light alone, but resumes its red color again in
the presence of both air and light.

These laws of Grotthuss found little appreciation among his contem-
poraries; they were entirely forgotten, just as the dualistic electro-
chemical theory of Berzelius was afterward abandoned. 40 Still we
must recognize the fact that the basic ideas which Grotthuss laid down
in his photochemical theses were not far removed from the most
modern views of physical chemistry, since the chemical forces of
affinity are essentially of an electrical nature.

The fundamental principle that fugitive dyestuffs fade behind
colored glass only by the action of those color light rays which they
absorb (complementary colors), but are preserved by the rays of their
own color (which they reflect), led later to the numerous photo-
graphic bleaching processes or color adaptation processes; 41 they fur-
nished the possibility of photography in natural colors.

It will be seen that Grotthuss did not consider the law of absorption
which he had found of great importance, for otherwise he would have
laid more stress on it. At any rate, he paid no more attention to this
subject in the subsequent years, but devoted his time to numerous
other chemical and physical subjects. For instance, a year before his

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169

death he wrote on the theory of Davy’s safety lamp and on his inves-
tigation of a meteorite. His many-sided and strenuous scientific labors
seem to have shattered his nervous system; in addition, he suffered
from a progressive abdominal disease, became dejected, and shot him-
self on his estate, January 14, 1822.

THE INVENTION OF A SELF-RECORDING PHOTOMETER WITH SILVER
CHLORIDE PAPER BY LANDRIANI IN VIENNA ( I 8 I 8 ) 42

At the beginning of the nineteenth century the light sensitivity of
silver chloride paper was well known, especially through the works
of Tom Wedgwood and Humphry Davy. We are indebted to Count
Marsiglio Landriani, of Vienna, who was Lord Chamberlain to the
Archduke Albert of Saxony-Dresden, for the first use of silver chloride
paper in the production of an automatic recording photometer with a
clock movement. Count Landriani devoted his leisure time to physics,
wrote on the thermometer, constructed self-recording machines for
the measurement of wind velocity, and so forth. He traveled a great
deal and lived in turn in Vienna, Italy, and France, published his
writings in both German and Italian, and was also correspondent of the
Academy in Paris. This versatile, learned gentleman died in 1 8 1 8.

His last publication was “Di due termometri, di cui uno in assenza
dell’osservatore indica il massimo e l’altro il ininimo di colore e del
lucimentro,” which appeared in the Giornale di fisica, Dec. 2, 1818,
Vol. I.

During some of his experiments he used silver chloride paper, about
which he spoke to Professor Traugott Meissner, in Vienna. Meissner
was an old Austrian, born 1778, who had worked as apothecary’s
apprentice and studied chemistry under Jacquin, in Vienna, about
1797. He was pharmacist from 1800 to 1814, then came to Vienna as
an assistant in chemistry at the Polytechnikum. He soon achieved his
full professorship. He was the inventor of heating with hot air and
wrote, among other books, a manual on general and technical chemistry
(5 vols., 1819-33). This work is one of the last to be published in the
nineteenth century in which a chemist supported the antiquated phlo-
giston theory. He was succeeded in his professorial office in 1845 by
the chemist Professor Anton Schrotter (1802-75), the discoverer of
red phosphorus, and died in Neuwaldegg, near Vienna.

In Meissner’s Handbucb der allgemeinen und technischen Chemie
(1820, II, 280, “Chemie der nichtmetallischen Stoffe, Abteilung A”)
mention is made of “the application of light.” Meissner writes:

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170

The property of light which causes different color substances to become
decomposed under development of heat furnishes us with a means of
measuring the intensity of light. On this is based the arrangement of the
photometer invented by Sir John L. Leslie (1766-1832). It consists of two
thermometers of equal size, the bulb of one having been blackened . . .

Landriani proposed another photometer based on the decomposition of
homsilver (silver chloride) by light, which consists of a round disk coated
with chloride of silver, covered by another opaque disk which is pierced.
It is covered in such a manner that the second disk is turned a little by
clockwork every half hour, which exposes at each turn a new portion of
the lower disk to the action of the light. In sunlight, different portions
undergo in this manner an unequal darkening, by which the difference in
the intensity of the light at different hours of the day can be measured.

This is undoubtedly the first description of a self-recording day-
light photometer using light-sensitive silver chloride paper, and Meiss-
ner evidently learned of it directly from Landriani and recognized
its value. The invention of the recording photographic photometer,
therefore, must be accorded to Landriani not later than 1818; the first
publicity about it was given by Meissner in 1820.

The Swedish inventor Georg Scheutz used chloride of silver paper
in 1832 for the recording of sunlight for maps ( Nord . Tidskr. f.
Fotogr., 1925, p. 70).

HERSCHEL DISCOVERS (iN I 8 I 9) THE PROPERTY OF HYPOSULPHITES
AS FIXATIVES FOR CHLORIDE OF SILVER

Sir John Herschel discovered hyposulphites and described their
properties in Edinburgh Philosophical Journal (1819, I, 8, 396). For
us the fact of particular interest is the statement that “muriate of silver,
newly precipitated, dissolves in this salt (hyposulphite), when in a
somewhat concentrated solution, in large quantity and almost as readily
as sugar in water.” It is curious to note that this observation of Herschel
was not utilized by his contemporaries or by later scholars who studied
the light sensitivity of silver compounds for the fixation of light images
on silver paper. Neither Daguerre nor Niepce knew of the fixative
property of the hyposulphites at the time of the publication of daguer-
reotypy in 1839, although Daguerre adopted its use in that year; even
Herschel’s contemporary, the scientist Talbot, experimented with
different salts for the fixation of his images on silver chloride paper,
but it never occured to him to try sodium hyposulphite. But when,
in 1839, the whole world discussed Daguerre’s invention and Herschel

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*71

learned of Talbot’s experiments, he published the announcement that
hyposulphite was an excellent fixative for chloride of silver.

In 1821 Faraday discovered that iodine in combination with oil-
forming gas (ethylene) forms a crystallizing compound when both
are exposed to sunlight. 43 He gives an account of

a triple compound of iodine, carbon and hydrogen. It was prepared by
exposing iodine in olefiant gas to the solar rays .... Crystals were
gradually formed; no hydriodic acid appeared to exist in the vessel, so that
the olefiant gas had not been decomposed, but merely absorbed by the
iodine. The triple compound of iodine, carbon and hydrogen was purified
by potash, which dissolved the uncombined iodine .... Mr. Faraday
considers this substance analogous to chloric ether. He proposes to call it
hydrocarburet of iodine.

This permitted the production of carbon perchloride direct from ethy-
lene and chlorine gas, if the resultant oil is exposed with excess
chlorine gas to the solar rays . 44

In the same year William Henry 45 found that marsh gas (methane)
is not decomposed by chlorine in the dark, but only in the presence
of light.

Kastner mentions, referring to Robison’s earlier statement, that
light rays which have penetrated water turn silver chloride blackish
purple, while light passing through nitric acid in the same time and
under identical conditions will scarcely turn the hornsilver gray, that
is, the latter absorbs much more of the chemically acting rays than
silver— a confirmation of Robison’s opinion (1787) 46

Witting and Zimmermann made experiments on the decomposition
of aqueous silver nitrate solutions. Ernst Witting (1800-1861) studied
the behavior of silver nitrate solutions toward some of the gases and
found 47 that carbonic-oxide, hydrogen, and phosphoreted hydrogen
gas effect a color change and precipitate even in the shade, while, on
the contrary, an aqueous solution of silver nitrate saturated with car-
bonic gas did not change color in the shade even after several days,
although in light a violet coloring showed after a short time— at first
without precipitate. 43

In 1823 Rudolf Brandes (1795-1842) investigated camphoric acid
salts more exhaustively and found that silver salts are white, but turn
brownish under light. 40

In 1821 a so-called “blood rain” fell near Giessen, Germany, which
caused Wilhelm L. Zimmermann (1780-1825) to investigate these

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172

aqueous meteors. He found in them a small salt content and organic
substances. He speaks in the course of his investigation of a curious
difference which the meteoric waters show toward nitrate of silver.
Sometimes the waters decomposed in a nitrate of silver solution became
turbid, at other times they did not. In the first case the turbidity
darkened by sun or daylight to bluish gray, violet, and finally formed
a blackish sediment. Zimmermann concludes that the chlorides pre-
dominated; the color changed to yellow-red, wine-red, and ended
with purple. Finally a violet-brown precipitate formed (chloride and
organic substances were present). 50

In the second case the Waters mixed with silver salt run through
the same cycle, from yellow-red to purple (predominance of organic
substances), or they remain unchanged and show only a suggestion
toward red (the water was deficient in organic substances and in
chlorides) .

For further experiments in photochemical processes we are indebted
to Johann Wolfgang Doebereiner, whose biography will be found
later in this chapter. In his Fneumatischen Chemie (1825, V, 103), he
states that a mixture of iodine, alcohol, and sulphuric acid loses color
rapidly only in sunlight and sets free long sulphur crystals.

In 1826 Doebereiner succeeded in reducing platinic chloride from
its solution by light, mixing this solution with another of neutral
tartrate of soda until it became turbid and then exposing it to sunlight.
The platinum was reduced almost entirely and deposited on the inner
surface of the tube in the shape of thin, greyish-black lamellae. When
he emptied the tube and then filled it with hydrogen, the reduced
metal assumed a beautiful silver color. In this process of reduction,
according to Doebereiner, the tartaric acid is changed into carbonic
acid and formic acid. He continued his labors in photochemistry later
with the greatest success.

DISCOVERY OF BROMINE (1826)

Bromine was discovered about 1826 by Antoine Jerome Balard
(1802-76), at that time lecturer in the school of pharmacy at Mont-
pellier. The incident which directed his attention to the mother liquor
left after salt had been crystallized out of the concentrated waters of
the neighboring salt marshes 51 is thus related by Karl Adolph Wurtz:

About 1824, when botanizing one spring morning near the edge of a salt
marsh, Balard noticed a deposit of sodium sulphate, which the coolness

FROM SEEBECK TO DAGUERRE

r 73

of the night had caused to crystallize out in a basin where someone had
left a quantity of mother liquor after separating common salt. The idea
of studying these mother liquors immediately took possession of his mind
and occupied it during the greater part of his life. In the course of his
subsequent experiments he was impressed by the peculiar coloration which
certain reagents developed in such mother liquors. He made the most of
this observation, and, following it up with a tenacity amounting to genius,
he had the good fortune to discover bromine. It was a great discovery.
Balard isolated a new simple body, not an insignificant rare metal hidden
in some little-known mineral, but a highly important substance destined
to rank between chlorine, which we owe to Scheele, and iodine, which we
owe to Courtois. Thus, the name of this young man of twenty-four was
placed at the outset of his career by the side of these illustrious names, and
there it has become immortal.

Bromine (“bromos,” Greek for bad odor), was the name Balard
gave to the new element on the advice of his teacher, Anglada, and
with respect to the behavior of the substance ( Chem . News, 1909,
LXXXXTX, 205).

Balard 52 describes in his report, mentioned above ( Annal . chim.
phys., 1826, XXXII, 361), different bromates, like potassium bromide:
“Nitrate of silver produces in hydrobromides a cheese-like precipitate
of silver bromide. This compound, which has a pale greenish-yellow
siskin color, turns black when it is exposed to light while still moist,
but less so than silver chloride.” Bromate of silver he found fairly
constant in light.

The use of silver bromide, however, was not introduced into pho-
tographic processes until after the publication of Daguerre’s process.

Balard’s life passed more quietly and he achieved greater honors
than Courtois, the discoverer of iodine. He was called from Montpellier
to the faculty of sciences in Paris and became a member of the Institute
of France.

FURTHER PROGRESS IN PHOTOCHEMISTRY

N. W. Fischer 53 was the first to publish, in 1826, the observation
that silver nitrate is reduced in light with varied color, according to
the nature of the admixed organic substances; in the presence of india
rubber the change is toward red-brown and dark violet; with sugar
it turns entirely black; with starch it shows a gray color. This supple-
mented Grindel’s observation on the photochemical properties of silver
albuminates.

FROM SEEBECK TO DAGUERRE

In 1826 J. L. Casaseca, of Salamanca, a pupil of Thenard, investigated
the action of nitrate of silver oxide on vegetable substances, partic-
ularly on solutions of rubber, sugar, starch, flour, wine, alcohol, nut-
galls, coffee, tea, licorice root. He found that especially tea, coffee, and
nutgall infusions rapidly reduce metallic silver from silver solutions,
and that ammonia, potash and soda promote this reduction. 64 “More-
over, light plays no role in this reaction, of which I have convinced
myself by a direct experiment.”

R. Brandes and Reimann carried on Zimmermann’s experiments with
silver nitrate solutions which contained one percent silver nitrate. In
these experiments water remained for a prolonged period in contact
with the respective organic substances, in order that it might absorb
the soluble ingredients, and was then treated with the silver salt. The
result of these experiments is recorded in the table on the following
page. 55 Brandes and Reimann conclude that silver nitrate is decomposed
by most organic substances when exposed to light and that the different
colored cloudiness and precipitates might be made useful for reactions.

SUCKOw’s WORK ON PHOTOCHEMICAL ACTION ( I 8 2 7 )

Dr. Gustav Suckow published, in 1827, a prize essay, De lucis effecti-
bus chemicis in corpora organica et organis destituta, in which he
discussed especially the processes of disassociation by light in organic
bodies (plants, etc.) and chiefly referred to earlier investigations by
other scholars of natural science. It was not until the enlargement of
this work in its second edition (1832) that the important and original
discoveries of Suckow were published.

GUSTAV WETZLAR DESCRIBES SILVER CHLORIDE AFTER BLACKENING IN

LIGHT AS SILVER SUBCHLORIDE ( I 8 2 8 ) ; OTHER WORKS ON SILVER AND

MERCURY SALTS

Gustav Wetzlar published, in 1828, his Beitrage zur chemischen
Geschichte des Silbers , 50 in which he concentrated his attention on
subchloride of silver. He was a practicing physician at Hanau (1799-
1861) and director of the Wetterau Society of Natural Sciences.
Since his investigations on silver chloride and its behavior toward light
were regarded as authoritative on the subject for many years, it is
necessary for us to describe them here in detail. In discussing the
different formations of subchloride, he mentions the action of light
on silver chloride. He states that until then blackened silver chloride

Change in Daylight

Substance
Which Was
Put in the
Silver Solution

After
12 Hours

After
24 Hours

After
3-4 Days

Change
in the Dark
after Two
Weeks

Green leaf

Reddish

coloration

Full red
coloration

Dark violet pre-
cipitation in the
clarified solution

Slight

violet

precipitation

Pollen of
camomiles

Do.

Yellowish red
cloudy solution

Slightly

brownish

sediment

Lycopodium

No change

Slight wine
yellow color-
ation

Brownish flocculance
in the yellow
solution

Yellowish

coloration

Cork

Reddish

opalescent

Brownish
red opal-
escent

Reddish opales-
cent without
precipitation

No change

Paper

No change

Weak violet
coloration

Purple colored
flocculance

Hardly

noticeable

change

Sugar

Weak brown
coloration

Strong

brown

Purple sediment
from a clear
solution

Violet color-
ation without
precipitation

Rubber

No change

Violet

coloration

Gray-violet

No change

Glue

Do.

Reddish

coloration

Reddish brown
precipitate from
the clarified liquid

No change

Ether, alco-
hol, or essen-
tial oils

Do.

No change

Reddish color and
separation of some
blackish flocculance

No change

Leather

No change

Slight yel-
lowish red
coloration

Brown sediment
from the decol-
orized liquid

Very slight
sediment

Raw vinegar

Slight reddish
turbidity

Increased

turbidity

Purple precipi-
tation

No change

Raw acetic

Weak grayish

Slight precipitation

Slight

acid from

brown

greenish

in the weakly

greenish

wood

turbidity

greenish liquid

sediment

1 76 FROM SEEBECK TO DAGUERRE

was held to be a mixture of metallic silver with silver chloride, which
theory was started by Scheele’s experiment according to which am-
monia dissolved the silver chloride and precipitated metallic silver.
Wetzlar observed, after twenty-four hours of action by sunlight on
aqueous silver chloride, a strong odor of chlorine (this, however, had
been established by Fischer in 1814); he found that silver chloride
blackened in light did not become lighter in nitric acid, which, accord-
ing to his opinion, would have to happen if the blackening were
brought about by metallic silver. He called the dark silver chloride
formed by light “silver subchloride.” This splits up not only in am-
monia but also when cooked in a strong solution of common salt. Iron
chloride and copper chloride also restored the white color of chloride
of silver. To this treatise of Wetzlar, Fischer replied in his Vber die
Natur der Metallreduktionen (1828), in which he asserted his just
claim to priority with regard to his article published in 1814.

Wetzlar had earlier, on October 26, 1827, published the fact that
silver chloride-sodium chloride crystallized from aqueous solutions,
is not sensitive to light. 57 “It is curious that while homsilver (silver
chloride) is the most sensitive of all silver salts to the action of light,
its compound with sodium chloride is not affected in the least by the
most intensive sunlight. The solution of the double salt suffers also
no change whatever in light.” This statement is of interest, because
Daguerre used a solution of silver chloride in sodium chloride at first,
in order to fix his photographs on metal with a solution of common
salt.

Eilhard Mitscherlich, born in 1794, in East Friesland, found in 1827
that ammonium nitrate of silver and sulphate remain unchanged in
the air by exclusion of light, but turn black in daylight. 58 Following
upon each other the sensitivity to light of several compounds was
discovered, namely: silver nitrite, by Germain Henri Hess, 59 professor
of chemistry at St. Petersburg; quinate of silver, by Etienne Ossian
Henry and Peisson; 60 borate of silver, by Heinrich Rose; 81 pyrophos-
phate of silver, by Friedrich Stromeyer; 02 perchlorate of silver, by
G. S. Serullas; 83 pyro-acetate of silver, by Berzelius; 64 lactate of silver,
by Pelouze and Gay-Lussac. 65

Lowig found that a solution of mercury bromide disintegrates in
sunlight into mercurous bromide and hydrobromic acid, “without
doubt under liberation of oxygen.” When sal ammoniac was added,
no decomposition was noticeable. 88

FROM SEEBECK TO DAGUERRE

Carbonell also wrote on the light-sensitivity of mercuric salts, par-
ticularly regarding potassium mercuric tartrate. 07 Harff wrote on
acetate, 88 oxalate-tartrate, pyro-tartrate, malate, benzoate, and citrate
of mercury. 69 E. G. Burkhardt also investigated these salts. 70 Willibald
Artus, professor at Jena, studied especially the mercurous iodides
( 1 8 3 6) . It is worth noting that these authors do not mention the work
of their predecessors which we have cited, men who had earlier de-
scribed the light-sensitivity of some of these mercury salts.

DISCOVERY BY DOEBEREINER OF THE SENSITIVITY TO LIGHT
OF THE OXALATE OF IRON OXIDE AND MANGANESE OXIDE

The researches of the celebrated chemist Johann Wolfgang Doeber-
einer on photochemistry are of the greatest importance. He occupied
himself at first with the platinum salts and tincture of iodine, and these
studies were followed later by many important discoveries, among
them the greater light-sensitivity of ferric and manganic oxalates.
Doebereiner was born near Hof, Bavaria, in 1780; studied pharmacy,
practiced it from 1 799 on at Karlsruhe, and devoted himself to the
study of natural science, especially chemistry. He established a chemi-
cal factory at Hof, but was compelled to abandon the venture after
two years. He continued his studies privately and was called to the
university at Jena in 1810 as professor of chemistry, pharmacy, and
technology, where he taught until his death, in 1849. He stood in
friendly relations with Goethe and the Archduke Karl August of
Weimar; his correspondence with them was published by Schade
(Weimar, 1 856) . At that time his invention of the ignition of hydrogen
by platinum sponge created the greatest kind of a sensation. We have
already reported in this chapter his earlier and less considered photo-
chemical studies. He continued them in 1828.

In 1828 Doebereiner described the light sensitivity of platinum
chloride in an alcoholic solution and the sodium platinum chloride
mixed with alcohol and caustic potash. 71 In 1831 Doebereiner also
communicated numerous valuable observations in his dissertation
Zwr chemischen Kenntnis der Imponderabilien in der anorganischen
Natur . 72 He found that the purple-red oxalate of manganese oxide
decomposes rapidly in light (as well as in heat) .

Of still greater importance is his discovery of the light-sensitivity
of ferric oxalate, published in the same article (1831); this photo-
chemical process was of lasting consequence in the subsequent inven-

FROM SEEBECK TO DAGUERRE

178

tion of cyanotype, platinum papers, and so forth, as well as for use in
numerous photometers.

Doebereiner observed that a solution of ferric oxalate remained un-
changed when kept for a long time and after being heated for several
hours. In sunlight, however, many bubbles of carbonic acid formed
in a very short period. The liquid gradually became turbid and de-
posited, under the constant generation of gases, small, shining, lemon-
yellow crystals of ferrous oxalate (he called the product “Licht-
Humboldtit”) . He also determined that for one equivalent of carbonic
acid, two equivalents of ferrous oxalate are separated. 73

At the same time Doebereiner stated that platinum chloride with
oxalic acid in light forms metallic platinum, besides carbonic acid and
muriatic acid; also that chloride of gold and oxalic acid decompose
more rapidly in the light than in the dark; further, that the brown
solution of sal-ammoniac of iridium is light sensitive when mixed with
oxalic acid.

BRACONNOT DISCOVERS THE REDUCTION OF SILVER NITRATE
BY PYROGALLIC ACID ( I 8 3 I )

Pyrogallic acid, which later became so important in photography
as a developer, was produced in a pure state by Henry Braconnot, pro-
fessor of natural history at Nancy, in 1831, 74 who also found that it
rapidly reduced metallic silver from silver nitrate solutions, while
gallic acid, on the contrary, reduced it only very gradually.

SUCKOw’s DISCOVERY OF THE LIGHT SENSITIVITY OF BICHROMATES
ON ORGANIC SUBSTANCES ( 1 8 3 2 )

In 1832 was published a photochemical work which, similar to that
of Link and Heinrich, had for its object a general survey of the chemi-
cal effect of light: Die chemiscben Wirkungen des Lichtes (Darmstadt,
1832), by the German scholar of natural science, Dr. Gustav Suckow,
who was professor at the University of Jena, as was Doebereiner.
Gustav Suckow was born at Jena, 1803, received his doctorate in
philosophy at the University of Jena, where he settled and became
eventually professor. His first publication was a dissertation on the
chemical effects of light on organic and inorganic bodies: De lucis
effectibus cbemicis in corpora organica et organis destituta (1827),
which had a second edition in German under the title Die chemiscben
Wirkungen des Lichtes (Darmstadt, 1832). We cannot consider here

FROM SEEBECK TO DAGUERRE

his numerous analyses of minerals, his works on chemical mineralogy,
on tests with blow pipes, or his textbooks on chemistry and mineralogy.
But still greater is the importance for the history of photochemistry
and photography of his experiments with potassium bichromate. He
divided the substance according to the phlogiston theory: “On the
phlogistic processes effected by light, which can be directly related
to mixtures of substances,” for instance, compound of chlorine and
hydrogen, and so forth.

Professor Suckow was the first to discover that potassium bichro-
mate, when mixed with an organic substance, is sensitive to light,
while it is admitted that the light-sensitivity of chromate of silver was
found by Vauquelin as early as 1798. The discovery of Suckow that
chromates are light sensitive even in the absence of silver when organic
substances are added is of special importance in photography. The
reference in question in Suckow’s book is, in effect:

When a solution of potassium bichromate and potassium bisulphate is ex-
posed to sunlight and the effloresced salt is sprinkled in different places
with powdered sugar, the most beautiful colored moss-like vegetation
forms. In this process the exposure separates a part of the oxygen of the
chromic acid, so that thereby the green (!) potassium chloride is formed.

Incidentally, he mentions the fact that this phenomenon occurs only
under blue and violet glass, not under yellow glass.

This discovery of Suckow was entirely lost sight of by the his-
torians of photography until this author recalled it to memory in 1880.
According to Suckow ( Die chemischen Wirkungen des Lichtes, 1832,
p. 35) nitrate of silver is reduced in solid form as well as in solution by
light, especially by violet, blue, and green light; after prolonged action
by light, small particles of metallic silver are deposited. He also men-
tions that the use of an aqueous silver nitrate solution mixed with gum
and india ink as a marking ink on linen, and so forth, is based on this
decomposition in light.

Concerning silver iodide Suckow writes elsewhere:

A partial reduction of the silver in silver iodide occurs after continuous
exposure to light, but more slowly than in silver chloride under the same
conditions and by simultaneous decomposition of the water. This takes
place by the action of colorless as well as of some colored lights, particularly
violet and blue, but not red and yellow; it turns at first to a brownish shade
and ends with the blackening of the salt.

i8o

FROM SEEBECK TO DAGUERRE

Jermesite loses, Suckow states elsewhere, its transparency in sunlight;
the turbidity commencing on the surface and gradually extending to
the inside. The other portion of Suckow’s book is devoted to the action
of light on plant and animal organisms, and has no special interest
for us.

liebig’s process for the removal of silver stains

Liebig, in 1833, had come so close to the discovery of a fixative for
silver chloride images that he could have answered without hesitation
the precise question: “How can the undecomposed silver chloride be
removed from a photograph on silver chloride paper so that the coated
paper will not darken further after the removal of the chloride of
silver?”

He described a “process for the removal of designs or stains made
with so-called indelible ink, nitrate of silver. 75 The process consisted
in treating the black parts with chlorine water until they became white
and then applying ammonium hydroxide. If one forgot to remove the
formed silver chloride by ammonia, Liebig added, the stains would
reappear, after drying, as black as before.

landgrebe’s and dulk’s collected works “on light” (1834)

George Landgrebe, bom in 1802, at Cassel, published in 1834 the
splendid collective work Vber das Licbt, vorzugsiveise iiber die chem-
ischen und physiologischen Wirkungen desselben (Marburg, 1834).
He lectured at that time (1826-37) without salary at the University
of Magdeburg, and later owned a chemical factory at Cassel. We have
quoted Landgrebe’s book extensively in this history.

In the same year F. P. Dulk published his dissertation, which is now
very rare, on photochemical actions: De lucis effectibus chemicis;
commentatio, qua vira illustratissimo T rommsdorfj ad festa doctor atus
semisecularia condecorundo gratulata or do philosopborum in univer-
sitate Regimontana, inter prete F. P. Dulk (1843).

Friedrich Philipp Dulk (1788-1851) was pharmacist and professor
of chemistry at the University of Konigsberg, East Prussia. His work
is worthy of particular notice, because he deals chiefly with the chemi-
cal action of colored light. He pointed out that there was a movement
to prove an opposite effect of the light action at both ends of the spec-
trum (see Ritter, and others, above) . Dulk tried to approach the subject
by a careful investigation of the behavior of various substances under

FROM SEEBECK TO DAGUERRE 181

colored glasses, which lasted for three months. His experiments dis-
closed the result that mercuric oxide under colorless glass (turning
black) had lost 0.9 percent of its weight, under violet glass 0.5 percent,
under green 0.2 percent, under red 0.1 percent. Chloride of silver did
not change color behind red glass, but under glass of other colors it
turned dark, without loss of weight. When Dulk found that his silver
chloride, which had turned dark in light, became white in a silver
solution of nitric acid (contrary to Fischer and Wetzlar), he concluded
that metallic silver is formed in light. Silver oxide was reduced only
under white, violet, and green glass, not under red. Dulk’s conclusion,
the most important part of which is recorded here, is as follows: “The
action of white light is strongest, then follows that of violet and green.”
He did not accept the theory of a different action of the opposite ends
of the spectrum on chemical compounds.

ALLEGED INVENTION OF PHOTOGRAPHY BY HOFFMEISTER ( I 8 34)

There must also be recorded the publication in 1834 of a visionary
scheme by the Reverend Philipp Hoffmeister for the production of
light tracings by means of “a varnish” (?). He was, however, unable
to produce any kind of proof or to approach as near the authenticated
production of light images at which Wedgwood or Niepce had arrived.
We would not mention this publication here, had not Hoffmeister,
in 1863, made the inexplicable claim that he was “inventor of photog-
raphy,” for which he had not the slightest justification.

This alleged invention of Hoffmeister excited only passing atten-
tion. Hoffmeister wrote an autobiography, which is included in the
continuation of Strieder’s Gelebrtenlexikon (1863, I, 61), to which
the Cassel daily newspaper Kasseler Tageblatt (Oct. 19, 1887), and
some photographic trade journals (Phot. Korr., 1887, p. 518; Phot.
Nachrichten, 1890, p. 387) called attention. In this biography Hoff-
meister claimed to be the inventor of photography; he states that to
him, not to Daguerre, belonged the priority to the invention, and
Hofrat Hennicke, the publisher of the Allgemeinen Anzeiger und
N ationalzeitung der Deutschen, vigorously supported his claims.

Hoffmeister’s original communication was published in the Allge-
meiner Anzeiger und N ationalzeitung der Deutschen (1834, No. 303)
under the title “Von den Grenzen der Holzschneidekunst, sowie
auch einige Worte liber schwarze Bilder.” He states:

Permit the undersigned, Hoffmeister, to give a few hints how by sunlight

1 82 FROM SEEBECK TO DAGUERRE

even paintings and copper engravings may be produced. Everybody knows
how some . . . colors are bleached by sunlight; imagine then a board
painted with such a color, upon which certain objects throw a shadow,
and expose the board to the solar rays; soon a monochromatic painting
will appear, which needs only to be varnished to be made permanent.
Further, one could coat a tablet with a varnish which dries at once in the
sun, but in the shade is not yet dry enough to take on a colored powder,
and so without much trouble a multicolored painting could be produced.

. . . Finally, the sun could be used as a tool to engrave on a copper plate
or in lithography, since the sun rapidly absorbs every moisture and either
accelerates a mordant (etching fluid) or destroys its strength; thus pro-
moting or not the taking up of the blackening by the stone (lithography),
according to whether certain parts are dry or not .... However, it is
quite probable that the same effects (as by sunlight) may be produced by
an intense fire, so that not every dull day would become also a holiday.

Professor Bezzenberger justly estimated the value of the claims in his
article “Ein angeblicher Vorganger Daguerres” (Phot. Nachrichten,
1890, p. 397), in which he stated that to the Reverend Hoffmeister
belonged only a minor place in the history of photography. Personally,
I believe the cited statement of Hoffmeister to be more the expression
of an ideal wish than the result of experiments. At any rate, there is no
mention of any practical result of his ideas. It was not until 1863,
twenty-four years after the publication of the daguerreotype process,
that Hoffmeister, in his autobiography, mentions that he had used an
unsized paper coated red with cochineal in his experiments, which
(ostensibly in the camera obscura? ) was bleached in the light parts.
By immersing them in size (glue), he had fixed the pictures. A critical
consideration of the merits of this invention discloses that: (1 ) Hoff-
meister gave no indication whatever in 1834 of the use of the camera
obscura; he did so many years later and, therefore, cannot prove any
claim to priority. (2) Cochineal papers are too insensitive to light to
give images in the camera; that fixation by sizing is entirely insufficient
and that Nicephore Niepce had tried unsuccessfully the use of colored
paper. (3) Hoffmeister’s idea to employ “a varnish” which would dry
instantly in the sun has evidently no real background, otherwise he
would have explained in his autobiography the details of his experience
with this varnish, as he did in the case of the cochineal paper. Hoff-
meister’s claim has therefore no practical value and can compete as little
with Wedgwood’s claim to priority as with those of Daguerre and
Niepce; indeed, Hoffmeister hoped even to achieve from a great fire

FROM SEEBECK TO DAGUERRE

i8 3

the same action as from sunlight, which shows that he had not reached
the level of experience of numerous earlier physicists who were work-
ing in the same direction.

fiedler’s dissertation (1835)

In 1807, at Adlersbach, Bohemia, was born Johannes Fiedler, who
published in 1835 the dissertation, written with such great profound-
ness, De lucis effectibus chemicis in corpora anorganica, which carries
the ingenious motto “Nihil luce obscurius” (nothing is darker [more
unknown J than light). In this work there is gathered a discriminating
digest of the material which had become known up to the year of its
publication concerning the chemical action of light on inorganic
bodies. The following tables, reproducing from the dissertation the
photochemical processes there reviewed, gives a faithful picture of
Fiedler’s work.

I. Chemical Actions Which Are Caused Solely by Light

Substances Which Were Used
for the Experiments

1. Carbon oxide + chlorine
1. Ethane chloride chlorine

3. Ethylene + iodine

4. Ethylene + bromine

5. Methane + chlorine

6. Ethylene + chlorine

7. Chlorine water

8. Starch iodide

9. Prussic acid + chlorine

10. Oxalic acid + hydrochloric acid (?)

11. Uranium chloride ( + organic substance)

12. Iron chloride ( + organic substance)

13. Copper chloride

14. Gold chloride

15. Platinum chloride

16. Mercury chloride

17. Mercurous chloride

18. Potassium or sodium chloroplatinate

19. Iron sulphocyanide

184

FROM SEEBECK TO DAGUERRE

Substances Which Were Used
for the Experiments

10. Ferric oxalate

zi. Manganic bioxalate

11. Platinum chloride + oxalic acid
*3. Iridium chloride + oxalic acid

24. Silver oxalate

25. Silver carbonate

26. Silver borate

27. Silver chloride

28. Red mercury oxide

29. Mercurous oxide

30. Gold oxide

31. Antimony sulphide and oxide

32. Sulphurous acid

33. Combustion

Result

Is decomposed and ferrous oxalate is
formed

Is decomposed

Is reduced to platinum

Is reduced to iridium

Is reduced to silver

Is partly reduced

Partial boric acid is liberated

Is changed to silver suboxide

Is changed to mercurous oxide

Is reduced

Loses oxygen

Lose oxygen

Quickly decomposes tincture of io-
dine in sunlight

Is retarded in light

II. Chemical Actions Which Are Caused jy Light and Heat

Substances with Which the Experiments
Were Carried Out

1. Mixture of chlorine and hydrogen

2. Bromine and hydrogen

3. Ferrocyanide of potassium and sodium

4. Gold chloride and oxalic acid

5. Silver phosphate

6. Silver nitrate

7. Brown peroxide of lead

8. Chloroxide )

9. Chlorous acid j

10. Sulphuric acid

11. Nitric acid

12. Gold- and silver-salts mixed with essen-

tial oils

Result

Combines with detonation
Combine to hydrogen bromide
Are decomposed
Reduced to gold

Loses one part of phosphoric acid
Gives off oxygen
Loses oxygen

Are decomposed into chlorine and
oxygen

Gives off oxygen (?)

Loses oxygen
Are reduced

Fiedler took little notice of the chemical effect of colored light, stat-
ing only that violet light exercises the greatest effect, which follows

FROM SEEBECK TO DAGUERRE 185

closely on that of white light, after which follow blue, green, and
red lights.

ACTION OF LIGHT ON MEDICINE

Theodor von Torosiewicz published, in 1836, at Lemberg, a very
remarkable article on the preservation of medicines in colored bottles. 78
He pointed out that for some time the necessity had been discussed
in chemical pharmaceutical journals of disposing of the glass receptacles
in the chemist’s shop and in the storage room in such a manner as to
protect their contents from the changing influence of sunlight.

It is well known to every pharmacist [^continues Torosiewicz] that not
only the preparations which lend themselves easily and quickly for mix-
tures such as chlorine water, hydrocyanic acid, animal Dippel-oil (bone
oil), etc., but also most of the vegetable powders, when kept in transparent
vessels, will suffer in time considerable change .... To obviate this evil,
wooden containers were preferred to ordinary glass vessels, and it was
recommended that the bottles in which liquids were kept be painted black
or that so-called hyalite (glass-opal) bottles be used for the storage of
medicines. Physicians always ordered that bottles be pasted with black
paper if the medicinal compound contained hydrocyanic acid. The homeo-
paths also must, according to prescription, preserve their globules made
potential with hydrocyanic acid in bottles completely covered with black
paper .... The black paint on glass vessels, however, rubbed off very
soon, and the black bottle was repugnant to the patient; hyalite bottles
were too costly, and their opacity was inconvenient.

Therefore, Torosiewicz, following the declarations of Scheele, Berard,
and Suckow that the color of silver chloride under red and orange
yellow glass is not changed, recommended the use of transparant,
golden-yellow, orange, or red colored glass vessels for the preserva-
tion of all light-sensitive substances. On account of their lesser cost,
he used yellow bottles and started a series of experiments, during which
he observed the behavior of various substances exposed to light and
their changes when contained in white and yellow glass vessels.

Chlorine water behind white glass became clear as water in eight
days and contained no trace of free chlorine; behind yellow glass it
remained still greenish after twelve days and retained all its original
properties. A solution of iron chloride in ether became discolored
behind white glass in twenty-four hours; behind yellow it remained
unchanged after twenty days.

1 86 ACTION OF LIGHT ON DYESTUFFS

Hydrocyanic acid became yellowish under white glass after twenty
days; under yellow, no change appeared after a month. Animal oil,
which among all the essential oils changes most rapidly when exposed
to light and air, remained as clear as water in a completely filled yellow
bottle.

Mercurous iodide mixed with lard, much used in medicine at that
time, turned dark on its surface in a minute behind white glass, and in
the course of fifteen minutes became almost grayish-black. Under
yellow glass, the salve assumed a somewhat darker, greenish color on
the side which was turned to the light after a full day’s exposure (the
yellow glass therefore did not protect it completely) . Doebereiner’s
compound of platinum chloride and lime water remained unchanged
under yellow glass for several hours; under white glass, it became
turbid within three minutes.

Chapter XVTII. special investigations in-
to THE ACTION OF LIGHT ON DYESTUFFS AND
ORGANIC COMPOUNDS (1824-35)

In Jacob Roux’s Die Farben, ein Versuch iiber Technik alter und
neuer Malerei (1824) it is demonstrated that the cause for the darken-
ing, fading, and cracking of oil paintings is partly the use of artificially
prepared oils and partly the selection and combination of the coloring
matter. Roux considered carmine not very durable, while he regarded
madder lake as the most permanent among vegetable colors.

He regrets that painters, with the exception of Rubens and a few
others, do not trouble themselves to acquire an exact knowledge of
paints and that even in many paintings by later artists, for instance, in
the portraits of Graff (1736-1813), the paints had become cracked,
faded, and darkened. On the change in painters’ colors effected by
light various statements are made by later authors.

Montabert found gamboge, chrome-yellow, indigo, and so forth in
wax perfectly stable, but not in oil ( Traite complet de la peinture, Paris,
1829, Vol. VIII). According to Knirim in his Die Malerei der Alten
(1839, p. 166), cinnabar in wax colors and dragon’s blood are durable
in air and light. George Field states that carmine and cochineal, which
change rapidly in light and air, remain unchanged for a half century

ACTION OF LIGHT ON DYESTUFFS 1 87

when light and air are excluded ( Chromatographie , 1836). Of chrome
yellow he writes elsewhere that it will keep unchanged a long time in
sunlight, but will darken in impure air; he also mentions many other
pigments.

Jean Boussingault writes, 1825, from Santa Fe de Bogota, where a
great deal of orellin (bixin) was prepared, some details concerning
the chemical behavior of this pigment. He relates that, while the Indians
and Caribbeans paint their skins with a mixture of fat and orellin, they
prefer chicha, a pigment made fromBignonia chicha, not only because
the latter is a more vivid red, but because it does not fade so quickly
in sunlight. 1

Schubler and Frank wrote, 1825, on vegetable pigments; 2 Decour-
demanche, pharmacist at Caen, recommended in 1826 that dried herbs
and flowers be preserved by exclusion of moisture, tightly packed and
kept from exposure to light. Vegetable powders, also, should be stored
in a dark place, in fully filled bottles which had been painted black,
because without these precautions the light would cause a change. 3 In
Buchner’s Repertorium fiir die Pharmacie (1826, XXIV, 287) there
is a postscript to this article, in which Decourdemanche remarks that
the action of light on thoroughly dried substances is not so energetic
as is generally supposed. The principal causes of the spontaneous de-
composition of organic substances are undoubtedly moisture and heat
(referring to herbaria). In sealed vessels and in completely dry air
(dried by quicklime) flowers keep for a very long time even under
the action of light. Professor Georges Serullas found that chlorine and
hydrocyanic acid combine in sunlight. 4

Dr. C. Sprengel, of Gottingen, experimented in 1828 with the
probable action of light on the soil of tillable land. 6 He states that by
the violet and the blue rays of sunlight the deoxidation of some of the
constituent parts is promoted, especially in the presence of organic
compounds, “so that, for instance, ferrous oxides form from ferric
oxide when (exposed to light) they come into contact with humus and
such like.” At any rate, sunlight plays an important role in the growth
of plants, which Sprengel investigated. He mentions that as a rule
vegetables grown in sunlight are more nutritious than those grown
in the shade because, he claimed, the action of sunlight promoted the
formation of a larger starch, albumen, gluten, and sugar content.

Later Sprengel dealt more fully with this subject, in his Chemie fiir
Landwirte F or s twine und Kammeralisten (1830).® He stated that the

1 88 ACTION OF LIGHT ON DYESTUFFS

presence of ferrous and manganous oxides in the soil were due to the
action of light, and he made the following assertion, but did not prove
it: “When light has unobstructed access to humus, carbonic acid and
water form on account of the retarded combustion of the fallen leaves;
when, however, the access of light has been checked by thick layers
of leaves in the forest, a more rapid combustion takes place with for-
mation of humus acid (??).” Apart from these hardly exact statements,
Sprengel offers many very interesting and valuable observations on
the dependence of the growth of plants on light.

Professor W. A. Lampadius collected in his small essay published
in 1 830, 7 Vber die durch Imponderabilien bewirkte Veranderung des
chemischen Verbaltens der Korper, among other matters, some obser-
vations on the action of light:

1. Kastner’s observations that lime exposed for a time to sunlight pos-
sesses a stronger force to promote the growth of plants than lime not acted
on by the sun. He published this observation in his Geiverbefreunde. It
would certainly be worth while to repeat this experiment . . .

2. The use of minerals decomposed by long exposure to the sun is pref-
erable to those reduced to small pieces mechanically. Lampadius hesitates
to attribute a great role to light with full certainty.

3. The bleaching of several fatty oils, which takes place when they are
exposed to sunlight in completely filled bottles.

4. The sudden formation of fatty acid which can be observed, for
instance, when fresh thoroughly washed butter is kept melted by sunlight
for fifteen minutes under the air-exhausted receiver of an air pump.

In 1831 Pierre Jean Robiquet investigated a light bluish-gray, very
durable colored substance and found that its color was due to silver
chloride blackened in light. He attempted to reproduce this color by
soaking some fabric in a solution of silver nitrate and then dipping it,
when dry, in a solution of calcium chloride or in chloride of lime and
exposing the surface covered with silver chloride to the action of
light, whereupon the color developed.

A dyer tried this experiment on a large scale, but failed for the fol-
lowing reasons: “If the color is to develop evenly in all parts, it is
necessary that all of the surface of the stuff be exposed to light at the
same time. The dyer in question could not accomplish this in his work-
room. He exposed only portions of the stuff one after the other to light,
and that caused the uneven appearance. Under favorable circum-
stances, Robiquet states, the experiment would be quite successful.” 8

ACTION OF LIGHT ON DYESTUFFS 189

Konrad Zier investigated, in 1832, among other matters, the behavior
of orange-red palm oil in light 9 and found that:

When palm oil is pressed into a narrow clear-glass tube, which is then
hermetically sealed at both ends and exposed to sunlight, the color of the
oil will scarcely be changed in the course of several weeks. The change
takes place more rapidly if water is added to the oil and it is shaken from
time to time after the heat of the sun has liquified it. When, however, light
and at the same time air are allowed to act on a very thin film of oil, the
bleaching will take place more rapidly, and the oil will finally turn entirely
white.

Lampadius repeated this experiment in the same year 10 and found
that a layer of palm oil, about one line high, in a glass dish was bleached
completely white under the action of the direct rays of the July sun
after scarcely twelve hours and that it had also lost its odor of violets.
The heat of the solar rays had completely liquified the palm oil during
the bleaching. In a heavier layer or in a not quite melted condition the
bleaching takes longer.

C. Merck presented, in 1833, a simpler formula for the production
of santonin, and found that its white crystals turned yellow in sun-
light. 11

In 1834 Herman Trommsdorff, Jr., after a searching investigation
of santonin, confirmed the findings that the colorless crystals do not
change in the air on exclusion of light, but turn yellow in a few minutes
when exposed to the solar rays. 12

In their investigation “Ober das Berberin” the Buchners, father and
son, discussed its usefulness for dyeing. 13 They stated:

A disadvantage of berberine yellow, as of most yellow vegetable colors, is
its rapid bleaching in sunlight. When a piece of paper coated with a solution
of berberine 14 is exposed to the rays of the sun for only a few hours, its
color will appear perceptibly faded, and this is also the case with colored
fabrics .... Contrary to all expectations those fabrics mordanted with
tin crystals faded still more than those colored only with berberine. Those
mordanted with copper vitriol faded rapidly; in those stuffs mordanted
with tannin acid the fading was less apparent, in fact, we would say that
they gained in beauty of color, at least silk and wool. Generally speaking,
silk, and often wool, retain their color for the longest time, and if they
change somewhat in sunlight, the color does not on that account become
more disagreeable.

Landerer, of Athens, reports that phosphorus containing oil did not

190

ACTION OF LIGHT ON DYESTUFFS

liberate any red phosphorus even after a year and a half in the dark,
while after three months’ exposure to light, much red phosphorus had
deposited on the sides of the glass vessel. 15

C. Henry and A. F. Boutron-Chalard found, in 1836, that light acts
quickly on nicotine and turns the colorless liquid to brownish yellow. 18
Berzelius found, in 1836, that the yellow and red coloring matter con-
tained in the leaves of the trees in autumn is a dark yellow, sticky oil,
a solution of which is easily bleached by light. 17

Of great value are the experiments in the art of dyeing made by
Michel Eugene Chevreul ( 1 7 86- 1 889) . 18 In his youth Chevreul studied
chemistry under Vauquelin, was professor of chemistry at the Lycee
Charlemagne; member of the Academie des Sciences, Paris, and of
the Royal Society, London, director of the Royal Gobelins tapestry
factory, and died at the age of 103 years, a foremost authority in the
field of the chemistry of fats and colors.

In these researches Chevreul made a close study of the changes which
the principal agents, such as pure water, air, sunlight, and heat produce
under certain circumstances on the dyestuffs fixed on fabrics. He in-
vestigated especially the part played by oxygen in the air and by
moisture in the decomposition of colors when exposed to light.

Chevreul describes his experiments as follows:

Cotton, silk, and wool yams and fabrics which had been dyed in curcuma,
safflower, orseille, indigo sulphate, indigo, and prussian blue were attached
to cardboard and exposed to direct sunlight under the following conditions:

1. In a bottle from which the air had been exhausted and which con-
tained calcium chloride.

2. In a bottle which contained air dried by calcium chloride.

3. In a bottle which contained air saturated with water vapor.

4. In the open air.

5. In a bottle containing pure water vapor.

6. In a bottle containing hydrogen gas dried with calcium chloride.

7. In a bottle containing hydrogen saturated with moisture.

The general results which were attained by these experiments are
as follows:

1. The indigo contained in the cotton, silk, and wool remains unchanged
when exposed to light in an air-tight chamber, while prussian blue in the
same fabrics under similar conditions turns white. Curcuma fixed in these
fabrics is changed in an air-tight chamber by the action of light, while
orseille remains constant.

ACTION OF LIGHT ON DYESTUFFS

191

z. It is commonly believed that wool has the greatest affinity for pig-
ments, while cellulose (cotton, linen, hemp) has the least. This view, how-
ever, is not correct in a general way, as is shown by the following: In a
dry, air-tight chamber the light has no effect on orellin when fixed in
cotton and silk, while when fixed in wool the effect of light-action is con-
siderable. In moisture light changes safflower in wool and silk after pro-
longed exposure, while cotton dyed with it retains its rosy-red color; the
only change which it then suffers is a shade toward violet. In moisture wool
and silk dyed with orseille are not changed by light, while cotton dyed
with it fades. Indigo-sulphate on silk exposed to light in an air-tight dry
chamber remains unchanged, but on wool and cotton it changes color.
In dry air and in the atmosphere silk treated with this acid changes, but
not nearly so much as other fabrics. Indigo fixed on fabrics shows under
the influence of light, dry air, and in the open air exactly the opposite
behavior from indigo-sulphate; the first is less stable on silk than on cotton
and wool.

3. In an air-tight chamber sunlight does not seem to affect indigo,
orseille and safflower. In dry air, however, the action of light produces
entirely different changes, but they are not equally noticeable in all pig-
ments. The change in prussian blue on cotton is hardly noticeable, but
more so in silk and wool dyed with indigo. Wool and cotton dyed with it
change little, silk, more. Silk dyed with indigo-sulphate fades, while wool
and cotton dyed with it change considerably. Orseille loses its color on
cotton, while on silk and wool it leaves a reddish trace. Orlean on cotton
remains very red, but is completely decolorized on wool. Curcuma yellow
and safflower red are totally decolorized on all three fibers. Light and moist
air, on the contrary, have little more effect on fabrics dyed with prussian
blue than light and dry air; the same is the case with wool dyed with indigo;
this also applies to the three fibers dyed with orseille and silk, but to orlean
only on wool and silk, to curcuma in all three. Light and moist air, on the
contrary, change much more than light and dry air, indigo-dyed cotton
and indigo-sulphate dyed oil on all three fabrics; particularly striking is
the difference of effect in silk and wool. Curcuma and orlean on cotton
are much more subject to change by light-action in moist than in dry air.
The action of light and of the atmosphere is about the same as that of light
and dry air on prussian blue, indigo, wool, and safflower. It is greater,
however, with indigo dye on cotton and silk, on indigo-sulphate on silk,
orseille, orlean, and curcuma. The effect is almost similar to that of light
and moist air on indigo-sulphate, on cotton and wool, on indigo, on cotton
and silk, and on orlean. The effect is stronger on orseille, safflower, orlean,
and especially on curcuma. Light and moisture bleach stuffs dyed with
prussian blue more rapidly than light alone. In addition there forms a

ACTION OF LIGHT ON DYESTUFFS

i 9 2

brown precipitate in a bottle filled with moisture, which does not form
in a bottle from which air has been exhausted and dried. Light and moisture
change curcuma, cotton, and wool dyed with orlean; the orseille dyed
cotton, while they bleach the safflower on cotton very little and the
orseille on silk and wool hardly at all. Fabrics dyed with curcuma, orlean,
safflower, and orseille behave in hydrogen the same as in an air-tight cham-
ber. Light, hydrogen gas, and moisture together show results similar to
those of light and moisture.

Regarding the theory of bleaching, it is demonstrated by this ex-
periment that, with the exception of the fabrics dyed with prussian
blue, none of the stuffs mentioned above can be bleached completely
by light and that only cotton dyed with curcuma, orlean, safflower,
and orseille could be bleached completely white in the open air.

In 1 849 Chevreul investigated the action of light on prussian blue
and found that in an air-tight chamber it liberates cyanogen by the
action of the sun, but it turns blue again in the dark, absorbing oxygen.

In 1839 the celebrated French chemist Jean Baptiste Dumas observed
the formation of trichloracetic acid in the action of chlorine on acetic
acid under the influence of direct sunlight. He found that dry chlorine
gas in a bottle with glacial acetic acid will not act in the dark, but
reacts slowly in daylight and rapidly in sunlight. On very sunny days
the reaction sometimes results in an explosion, when upon opening the
bottle the gas which had formed escaped with force ( Annal . cbim.
phys., LXXIII, 75; Jour. f. prakt. Chem., XVII, 202). This discovery
gave the impetus to a series of photosyntheses.

RETROSPECT

When we review the efforts and tendencies of the experimenters
who devoted their time in the epoch just covered to the chemical ac-
tions of light, we must conclude that the utilization of photochemistry
for the production of light images, either by contact or in the camera
obscura, had been relegated to the background and almost completely
neglected. Photochemical processes were studied, sometimes in the
interest of the theory of light, sometimes in the realization of their use
in pharmacy or chemistry. Regardless, however, of the numerous
highly important observations on the nature of photochemical effects,
their full significance was not recognized until much later. The pro-
duction of photographs and their flxation had not advanced beyond
the early experiments of Schulze or Wedgwood. Indeed, in the writings

JOSEPH NICEPHORE NIEPCE 193

of the scientists of those days there is no indication of an earnest effort
for the solution of these problems.

So much the greater, therefore, is the merit of the two French ex-
perimenters Niepce and Daguerre, who for decades quietly worked
with astonishing persistence toward the production of light images in
the camera obscura and their fixation, as well as on the production of
printing plates by a photographic process. The world was indeed sur-
prised to the utmost by the publication of the daguerreotype process
in 1839. How the invention of Niepce and Daguerre developed from
unimportant beginnings is told in the following chapters.

Chapter XIX. Joseph nicephore niepce

Joseph Nicephore Niepce (1765-1 8 33) 1 may be named the inventor
of photography in the camera and the inventor of heliogravure, owing
to his having etched asphalt-covered metal plates. It was he who con-
tributed the actual photographic part of the procedure when he joined
with Daguerre in labors which led to the invention of the daguerreo-
type process, named after the latter. This process produced positive
images in the camera by relatively short exposures to light. Niepce
came from a rich bourgeois family of good standing which owned
several estates and also a town house at Chalon-sur-Saone, where he
was born. 2 His father was a lawyer and king’s counsel. His firstborn
child was a daughter. Then followed Claude Niepce (1763-1828)
and Nicephore Niepce, who was two years younger. Nicephore and
Claude lived in intimate fellowship, not only in their youth, but also
throughout their later years. A portrait of Joseph Nicephore Niepce
drawn by his son Isidore was reproduced from a line etching in La
Lumiere of July 6, 1851.

A portrait of Claude was found only recently by Potonniee and
published in the Bulletin de laSociete frangaise de Photograpbie (1929,
p. 195). The youngest brother Bernhard (1773-1807) plays no part
in the history of photography.

Nicephore and Claude received a thorough education in the Catholic
Seminary of the “Peres de la Congregation de l’Oratoire.” Nicephore
was destined by his father for the priesthood, and taught at the Semi-
nary after having finished his studies. Then came the French Revolu-
tion; the order was dispersed. His family, rich and suspected of royalist

i 9 4 JOSEPH NICEPHORE NIEPCE

sympathies, had to leave Chalon. The National Convention at Paris
decreed (September 28, 1791) that all French citizens between the
ages of sixteen and twenty-five were to report for military duty in
order to attain the rank of sublieutenant. When his father died, in
1792, Nicephore tried to avoid the suspicion connected with his family
by joining an infantry regiment. He became lieutenant on May, 1793,
in the army sent to Italy and took part in the Italian campaign of 1 794.
He contracted typhoid fever, then very prevalent, which forced him
to resign his commission and which ended his military career. Return-
ing to France, he lived in Nice, where he married and became, in 1 795,
a member of the district administration. His brother Claude entered
the French navy. Both brothers returned to their paternal home at
Chalon in 1801, where they constructed a machine to be used as a
motor for large boats. The motive power was derived from the ignition
of lycopodium powder mixed with air. They called their machine
“pyreolophore” and obtained a patent for the invention by a decree
of Napoleon, dated Dresden, July 20, 1807. The brothers Niepce
also occupied themselves with the production of indigo blue from
dyer’s woad (isalis tinctoria), to which the French government gave
recognition; but they were unable to produce a sufficient quantity to
satisfiy the demand for this dye extract.

Meanwhile, the invention of lithography was attracting much atten-
tion in Germany and France. Lithography was invented in Munich,
1797, by the Bohemian Alois Senefelder (1771-1834) and is fully
described in his celebrated Lehr buck der Lithographie, which appeared
in 1818. He obtained the lithographic stones at Solnhofen, Bavaria,
where later a monument to Senefelder was erected.

In 1802 Senefelder took his invention to France, but he met with no
success. It was not until 1812 that Count Charles Philibert de Lasteyrie-
Dussaillant, a well-known French agriculturist and son-in-law of
General Lafayette, interested himself in lithography and won for it
success. The Count traveled to Munich in that year to study the new
art, but had to return to France, owing to Napoleon’s unfortunate
campaign in Russia. After the Restoration (1814) he again visited
Bavaria, engaged workmen, purchased lithographic utensils, and re-
turning to Paris started a lithographic establishment. The process was
this time received with great enthusiasm, and many persons exploited
the method.

Nicephore Niepce interested himself in lithography and experi-
mented with the use of a local limestone for this purpose, as his son,

JOSEPH NICEPHORE NIEPCE 195

Isidore Niepce, related many years later; 3 he coated the stone with
varnish, engraved designs on it and etched them with an acid. The
stones at his disposal lacked the required fine and regular grain. He
therefore substituted pewter plates for the stones. It is only through
the later communications by his son that we learn that Nicephore
Niepce coated plates with a varnish of his own composition and ex-
posed them at the window under designs which he had made trans-
parent to light. Since Nicephore took only his brother and son into
his confidence concerning his experiments, there are no documents
of any kind extant for our study. It is certain, however, that the
brothers spent more of their time from 1 8 1 3 to 1 8 1 5 on their mechan-
ical inventions, particularly with the pyreolophore, than with helio-
graphic experiments. Claude Niepce moved to Paris in 1816. This
restricted Nicephore in his experiments to his own endeavors, and he
returned to the development of lithography. The progress of his work
is found in the correspondence with his brother Claude, which contains
important documents for the history of photography. 4 In his letter
of April 1 , 1 8 1 6, he expressed the hope that he would be able to fix the
colors of a picture; on April 12, 1 8 16, he spoke of a kind of an artificial
eye, which is nothing but a camera; on April 22, 1 8 1 6, he wrote that he
had accidentally broken the lens on his camera; on May 5 he com-
plained of the difficulties he had in procuring a new lens. Fortunately,
he found a solar microscope of his grandfather’s with a lens of focal
length suitable for his camera.

We learn from his letter of May 5, 1816, of his first exposure with
a miniature camera he had constructed. He obtained “with the process
of which Claude knew” a negative image on white paper, which he
could not fix. Most likely he worked with silver chloride. In his letter
of May 9, 1816, he wrote that it was not necessary to have sunshine
for exposures.

On May 19 Nicephore wrote: “I inclose in my letter two etchings
made by the process which you know.” According to Fouque this
should be recorded as the first mention of a heliographic etching, but
the following contents of the letter indicate that the reference is to
photographic silver chloride images which were not fixed (Potonniee,
p. 89).

F. Paul Liesegang writes to the author of this work:

Niepce speaks in his letter of May 19 actually of “gravures” (Fouque,
pp. 67-68). But I am certain that he deals with images on paper. At the
close of the letter he calls the pictures “retines” and advises his brother to

1 96 JOSEPH NICEPHORE NIEPCE

place them in a book between two pieces of blotting paper, since the images
were not fixed. In his letter of May 18 Niepce speaks of paper as the picture
carrier. He enclosed in this letter what he called “epreuves” (proofs) of
four exposures (pp. 69-70 in Fouque, in which letter paper is mentioned).
It must b e remembered that the subject was a new one, and terms were not
yet established. The word “gravure" was adopted by Niepce, probably
because he compared the negative impression of his fledgling exposure with
a print which had already furnished him with this method of reproduction
(Fouque p. 65 ) . In his letter of June 2, 1816, Niepce refers again to the four
proofs which he sent on May 28 and again calls one of the pictures on this
occasion “gravures” (Fouque p. 72). He explained to his brother the
peculiarities of the images, on account of their unusual appearance, for
they were negatives, i. e., the position of objects was reversed as to right
and left. The exposures were made by Niepce from the window of his
laboratory opposite a low-roofed outbuilding on which was a dovecot.

On June 2 Niepce writes that it was impossible to find a substance of
greater light sensitivity. He had tried to fix images on metal plates by
the aid of certain acids, but the light did not noticeably influence the
action of the acids. He therefore treated the metal plates in the camera
during the exposure with acids, hoping that the images would be etched
by the action of light. He expected a great deal from such a process, which
would produce plates from which reproductions could be obtained. It
appears from his letters of June 16 and July 12, 1816 (Fouque, pp. 80-81)
that he continued these experiments on stone, but without success.

The nature and method of Niepce’s experiments are indicated in
his letter to his brother Claude, dated June 16, 1816. He writes:

I have read that an iron chloride solution in alcohol, which is beautifully
yellow, bleaches in sunlight and recovers its original color in the shade.
I coated a piece of paper with this solution, which I allowed to dry; the
portion exposed to daylight bleached, while the parts protected against the
light remained yellow. But this coating absorbed too much moisture from
the air; I did not continue to use it, because accident furnished me with a
better substance. When a piece of paper is coated with a layer of Mars
yellow— yellow iron oxide— and is exposed to chlorine vapors, it turns a
beautiful yellow and bleaches more rapidly than the above (iron chloride).
I have placed both in the camera obscura . . . but could not produce a
light image; perhaps I did not wait long enough.

Niepce also tried to bleach manganese peroxide by light. He wrote,
April 20, 1817, that he had given up the use of silver chloride and in-
tended to use another substance. It appears from the same letter that he
had read in a work on chemistry that guaiacum, which is yellowish gray,

JOSEPH NICEPHORE NIEPCE 197

turned beautifully green by exposure to light. It took on new proper-
ties, and in this condition a stronger rectified alcohol was required for
dissolving it than in its original state. He coated paper with guaiacum
and produced, certainly, a light image; but his efforts to fix it with
alcohol were fruitless. He also read in the French edition of Klaproth’s
Dictionnaire de cbimie that A. Vogel described in detail the light-sensi-
tivity of phosphorus. 6 He hoped that by the use of “Alcohol de Lam-
padius,” namely, carbon disulphide, he could fix the image. Niepce
stated that in such a solution only the white phosphorus was soluble,
not the red phosphorus which is formed by light. 8

He worked indefatigably to produce a thin layer of phosphorus on
stone; he expected to attain with this substance what he failed to ac-
complish with the acids, namely, to etch an image on stone by light in
the camera obscura. On this experimenting, which evidently kept him
very busy, he reports in letters dated April 20, April 30, May 30, and
June 7, 1817 (Fouque, pp. 89-94). He now gave up these experiments,
in the course of which he had burned his hands, and applied himself
to the use of guaiacum, with which he had previously dealt in the
letter of April 20, 1817.

This seems to indicate that Niepce was influenced by the photo-
chemical investigations of his time and that his idea in using asphaltum
as a light-sensitive substance may be traced to the German chemist
Hagemann, who was the first to investigate guaiacum in 1782, and to
other scientists who favored the continued investigation of its light-sen-
sitivity. 7 Niepce had tried, according to his letters, to fix light pictures
on guaiacum with alcohol, although unsuccessfully; the apparent
change of color in the guaiacum, however, permitted no doubt of the
evident action of light which had occurred. That numerous other resins
were sensitive to light had been already demonstrated in 1782 by
Senebier. In his experiments Niepce probably happened on asphaltum,
which he undoubtedly had on hand, because lithographers use asphal-
tum varnish for coating the stone, and, as is well known, most of the
varnishes used as etching grounds then, as now, contain asphaltum.

niepce’s optical instruments 8

Niepce constructed three small cameras when, in the spring of 1816,
he began his experiments in heliography; one camera six inches long
with a sliding lens barrel, a miniature one, the size of a matchbox, and
another between these two sizes. In the museum at Chalon five large

198 JOSEPH NICEPHORE NIEPCE

cameras are preserved, which undoubtedly date from a period after
1826. Noteworthy among them are one with a leather bellows and
another with an iris diaphragm. It seems that Niepce is entitled to the
claim of priority for both accessories.

Uninformed concerning the experiences and advances of the pre-
ceding few decades in the field of optics as applied to the camera
obscura, Niepce used simple condensing lenses as objectives in his first
experiments. He learned to control the objectionable lack of sharpness
in the picture images to some extent by the use of a diaphragm. Unable
to overcome the excessively long exposures, which he had hoped to sur-
mount by the use of a condensing lens, he decided that it was impossible
to find a useful process of greater light-sensitivity and for a time aban-
doned further experiments with the camera. He returned to the use
of the camera in 1826, using the meniscus prism of the Parisian optician
Chevalier, which was a total-reflection prism, the cathetal faces being
curved, that is, ground hollow. Evidently dissatisfied, he passed on to
experiments with the “megascope,” an apparatus which was also made
by Chevalier, a kind of a camera obscura which was to serve him for
the reproduction of copper engravings, and so forth. This also brought
him no success. He was not discouraged, however, and realized that

among the principal means for improving the process, those concerning
optics must be put in the first rank. I was deprived of these resources in
the few essays I made with the camera, although I strove to do my best by
means of certain combinations. But it is with apparatus of this kind, per-
fected as much as possible, that a faithful image of nature may be obtained
and conveniently fixed £“Memoire” of his process which Niepce left with
Francis Bauer— written and dated Kew, December 1827J.

He investigated the possibilities offered by Chevalier’s lenses of all
kinds. He experimented with a lens of 24 inches focal length, also with
four lenses of 3 inches diameter and 12, 18, 30, and 36 inches focal
lengths; he seems to have worked with many combinations of lenses.
In 1828 he ordered from Chevalier two Wollaston periscopic lenses,
of which he undoubtedly learned during his stay for several months
in England. Chevalier also furnished him with an achromatic lens.
While the periscopic lenses furnished markedly better results than
his previous appliances, he still had to be content with exposures lasting
all day. He even used two lenses of 6 inches diameter and 24 inches
focal length in biconvex form, according to Chevalier’s recommenda-

JOSEPH NICEPHORE NIEPCE 199

tion, and from these expected to achieve success, by restricting himself
to a small field, but in this also he failed to obtain satisfactory images.

His last hope was Daguerre, who, as he had known for some time,
had worked on the improvement of the optics for the camera obscura.
It appears from a letter of Niepce to the Paris engraver Lemaitre that
Daguerre had offered to collaborate with him. In the hope of overcom-
ing his difficulties with the exposure by the aid of Daguerre’s lens,
Niepce accepted and this brought about the contract of December 14,
1829, which is discussed later in detail. All Daguerre had to offer, how-
ever, was an achromatic periscopic lens, undoubtedly made for him by
Chevalier, such as he used later on his cameras. The discovery of this
secret must naturally have been extremely disappointing to Niepce.
Daguerre himself affirmed in a footnote to his paper of 1839 that
Niepce’s hopes were not fulfilled. The road to further development
was not clearly indicated; it was necessary to find a material of greater
light-sensitivity.

In 1817 Claude Niepce went to London in order to sell the “pyreolo-
phore.” Very little is known about the progress of heliography during
this time. There are no letters of Niepce preserved from July, 1817,
to May, 1 82 6, 9 only some letters from Claude to Nicephore, which
are contained in Fouque’s La Verite. Claude, in his letter dated Decem-
ber 31, 1818 (Fouque, p. 10 1) speaks of a new substance from which
Nicephore expects much, but as to the nature of this substance he
(Claude) cannot guess. He writes in a similar manner on August
24, 1819 (Fouque, p. 102). On January 22, 1819, Claude writes
(Fouque, p. 104) that the new process seemed to have the advantage,
if it succeeded, that it would give permanent images (fix them). It
appears from Claude’s letter of March 17, 1820, that Nicephore used
a varnish and treated it with an oil (asphalt process). From the letter
of April 21, 182 1 (Fouque, p. 106): “The main point was to find a
means by which, once the image was obtained, it could be retained
unchanged.” In that lay the greatest difficulty. This establishes the fact
that in 1821 Niepce could not produce fixed photographic images
(Paul Liesegang).

At this time Niepce worked diligently in his country house at Gras,
near Chalon-sur-Saone, on his photographic experiments. Niepce’s
town residence at Chalon was later converted into a museum for his
works and adorned with a tablet commemorating his invention.

200 JOSEPH NICEPHORE NIEPCE

DISCOVERY OF PHOTOGRAPHY IN THE CAMERA; NICEPHORE NIEPCE PRO-
DUCED IN 182 2 THE FIRST PHOTOGRAPH ON GLASS IN THE CAMERA,

FROM NATURE, BY THE USE OF THE ASPHALT PROCESS

A letter from Claude Niepce in London, dated July 19, 1822, to his
brother Nicephore in answer to one of Nicephore’s, expresses his joy
at the good news of Nicephore’s success in the production of light
images in Chalon-sur-Saone. Claude’s letter reads:

General Poncet must be equally enthusiastic about the beauty of your
discovery, of which your renewed success has given me the greatest satis-
faction. I have read and re-read with admiration the interesting details
which you had the kindness to send to me; I see you before me, also my
dear sister and my dear nephew, attentively following with your eyes the
wonderful work of the light, and I believe that I also saw the same picture
which I recall with pleasure. How much I hope, my dear friend, that an
achievement so beautiful and so interesting for you and for science may
have a full and lasting result.

This letter contains in the first place the definite indication of the
successful photograph of Pope Pius VII (the copy of a copper engrav-
ing) and speaks obscurely of a “point de vue”; the correspondence of
the brothers shows their great concern about the necessity for secrecy,
which tends to ambiguity. Potonniee urged the year 1822 as the birth
year of photography in the Bull. Soc. franp. d. phot. (1921, p. 312)
and his Histoire (19 25, p. 102), pointing out that Niepce distinguished
in his letters between printing from transparencies and the “veritable
photographs,” that is, made in the camera, which latter he was ac-
customed to call “points de vue.” Now, Claude writes in his letter of
July 19, 1822, of “points de vue.” This letter was considered by
Potonniee “irrefutable evidence” to prove that the invention of an
exposure from nature was produced with the aid of the asphalt process
by Nicephore Niepce in 1822. He disputed the views of Fouque and
other older historians, who, in their earlier reading of this letter, were
misled because they saw in the letter a definite explanation of the
Pope’s portrait reproduced from a copper engraving by the printing
process. According to Potonniee, the “points de vue” were the veiled
reference to a camera exposure by Niepce of his courtyard in Chalon,
which was reproduced by the asphalt process through a window on
which a birdcage, and so forth, rested; this picture was supposed to
have been taken in the camera and to have been fixed in the known
manner. It should be pointed out here that Isidore Niepce, the son of

JOSEPH NICEPHORE NIEPCE 201

Nicephore Niepce, many years later made the following remark from
memory: “The pictures mentioned were produced by the asphalt
process, and in the family the tradition existed that the year 1822 was
the year of the invention of photography by Niepce.” Other proofs,
besides the letter cited above in this chapter, are, however, not avail-
able. The year 1822 was the date inscribed on the tablet on Niepce’s
home in order to establish the date of the invention. Lemaitre, the
engraver, who was later in frequent contact with the Niepce-Daguerre
Company, also accepts 1822 as the year of the invention (Bull. Soc.
pang. d. phot., 1856, p. 41). And so the author of the present history
will also assign 1822 as the year in which the brothers discussed between
them secretly the first successful “photography in the camera”; but
the element of doubt as to this conception cannot be entirely sup-
pressed, the establishment of 1822 as the year of the invention of
photography in the camera being chiefly based on the statements of
Niepce’s son, Isidore, whose recollections were not published until
many years later.

The result of this exposure in the camera of 1822 has never been
found, and Potonniee bases his statement on the philological interpre-
tation of the letter, dated July 19, 1822, which after all has some claim
to plausibility. In any event, the asphalt images or pictures were per-
manent and fixed. The copies of copper engravings produced in 1822
on light-sensitive asphaltum-coated plates were certainly very beau-
tiful and sharp, as every expert knows who has used this process.
Therefore, it is easy to understand why General Poncet was so en-
thusiastically impressed with the beauty of Niepce’s discovery; he
had before him the reproduction of an outline drawing, which no
doubt represented the heliographic process discovered by Nicephore
Niepce and which was based on the asphaltum process. The mysterious
phrase “point de vue” in Claude’s letters Potonniee endeavored to ex-
plain by a philological interpretation, as is stated above. Other earlier
competent historians read into this letter, the contents of which are so
veiled and nebulous, an entirely different meaning. The most eminent
of Niepce’s biographers was Fouque, who was the librarian of the
library at Chalon. He defended fanatically Niepce’s claim to priority
for the invention and published the result of his investigation in his
now rare book La V erite sur /’ invention de la photographie (1867).
He arrived at an entirely different conclusion. He read one hundred
and one letters in the course of his studies— some written by Niepce,

202 JOSEPH NICEPHORE NIEPCE

others addressed to him. For all the details known about Niepce’s life
we are indebted to Fouque, which is emphasized also by Potonniee
(Histoire, p. 74) . Ninety-three of these letters are preserved to us;
therefore Fouque had examined the majority of them. He also printed
the letter of July 19, 1822, which we have quoted.

But Fouque, the most eminent of Niepce’s biographers, read into
this letter which is still extant, something entirely different from
Potonniee. The letter in question is nebulous and secretive; it shows
a carefulness not to divulge anything. But it plainly indicates that the
beauty of the discovery and the novel successes elated General Poncet.
Fouque, as well as many other historians, recognized in this remark
an allusion to a photographic copy (that is, contact print) from a trans-
parent engraving, representing Pope Pius VII, not a photograph pro-
duced in the camera. This furnishes us, then, with a very authoritative
view of the most notable student of Niepce’s history. Claude writes
nothing in 1822 about the method of production. But Isidore, the son,
in an unpublished manuscript, writes, as Potonniee quotes, that his
father used at that time asphaltum on glass plates, and he adds: “It is
by the use of this substance that he (Nicephore) obtained in 1822 the
admirable reproduction of Pope Pius VII, which he presented as a
gift to his relative General Poncet de Maupas” (Potonniee, p. 104).
He says nothing of an exposure from nature. It is very important to
note that Isidore was quite clear on the point that the letter of July
19, 1822, refers to this reproduction (copy) in the form of an image
on glass, not an exposure from nature in the camera. Potonniee differs
from this, but it is possible that Fouque’s view is correct and that would
not contradict the opinion of Isidore. It is interesting to note that the
conscientious physicist Arago in his great historical introduction
(1839) to the report on the year of invention of daguerreotypy evades
this question.

Whether the half-successful trial of an exposure in the camera in
1822 took place is not quite certain. Arago, in his report of 1839,
established generally Niepce’s claim to priority for the production
of photographic pictures by the asphaltum process. He stated that
Nicephore Niepce invented photography with the asphaltum process
and that he was the first to produce pictures by the aid of a camera. He
also records, however, that exposures in the brightest sunlight required
twelve hours and that the process was not fit for practical use.

JOSEPH NICEPHORE NIEPCE 203

It should be noted that every photochemist who has experimented
with Niepce’s process knows that such asphaltum images on glass could
have produced only crude results compared with an exposure from
nature, producing, as is known, a negative. No one more clearly than
Niepce himself recognized that the road he took in making exposures
in the camera could not lead to practical results; for the reason stated
above, therefore, he turned to new researches on the light sensi-
tivity of silver iodide plates, which afterward led, with the work of
Daguerre, to the perfection of the invention of photography. At this
time it must be remembered that Wedgwood and Davy were the first
to recognize the fact that silver papers yield gradations according to
the different intensity of the exposure to light, and to realize the pos-
sibility of the reproduction of middle or half tones, although both
Wedgwood and Davy failed to accomplish their object— to produce
images in or by the camera.

CELEBRATION OF THE CENTENARY IN HONOR OF THE INVENTION
OF PHOTOGRAPHY BY NIEPCE

Marking the year 1822 as that in which photography was invented,
a centenary celebration in honor of the inventor Nicephore Niepce
was held in Paris, on which occasion the memory of Daguerre also
was highly honored.

The Societe frangaise de Photographic decided, in connection with
the historical significance of the year 1822, to honor Niepce and
Daguerre during the International Congress of Photography held at
Paris in 1925 by a celebration. At a festival session at the Sorbonne,
July 2, 1925, under the patronage of the French President Doumergue,
the memory of Niepce and Daguerre, who have laid the basis for the
photographic art, was commemorated. The official speaker of the day,
Potonniee, said: “Niepce’s experiments led in 1822 to the photographic
reproduction of his own house on a tin (or pewter) plate, and thus
the art of photography was invented.” The city of Paris contributed
a commemorative tablet with the inscription: “Here stood, from 1822
to 1839, the diorama of Daguerre, with his laboratory, where he, in
collaboration with Niepce, discovered and perfected daguerreotypy.”
The underground railway necessitated the tearing down of this build-
ing, and a marble tablet was affixed to the wall of the barracks of the
Garde Republicaine in the Place de la Republique.

2 04 JOSEPH NICEPHORE NIEPCE

THE FATE OF THE SUCCESSFUL ASPHALTUM COPY ON GLASS
OF THE YEAR 1822

General Poncet, a cousin of the brothers Niepce, was so well pleased
with the asphaltum portrait of Pope Pius VII (a print from an engrav-
ing which had been made transparent), which had been made in his
presence at Gras, near Chalon, that he asked for it as a gift from Nice-
phore Niepce. He took it with him on his travels, and when one day
an admirer of the glass plate accidentally dropped it, it broke. Thus
was lost to us the first permanent photograph made by Niepce, which
had passed into other hands. 10

NICEPHORE NIEPCE DURING THE YEARS 1 82 3-26; ETCHINGS
ON METAL BY HELIOGRAVURE IN 1 826

Three years, from 1823 to 1825, inclusive, were spent by Nicephore
Niepce in experimenting with the production of asphaltum photo-
graphs on glass and on metal. In the Niepce Museum there is preserved
a tin (or pewter) plate with the heliographic reproduction of Christ
on the Cross, by the asphaltum process, which is inscribed “Dessin
heliographique, invente par J. N. Niepce 1824.” This date should
more correctly read “1826.” The inscription is due to his son Isidore,
who affixed it long afterward.

From 1826 dates the production of a heliographic pewter plate repre-
senting Cardinal Georges d’Amboise, Minister of Louis XII. Niepce
had etched this heliographic plate in the summer of 1826 and sent it
on February 2, 1827, to the engraver Lemaitre, in Paris, who returned
printed proofs of the plate to Niepce on March 5, 1827. The size of
the original, preserved in the collection of the Societe franchise de
Photographic, in Paris, is 13.2 X 16.2 cm. (5.2 X 6.3 inches).

The date 1 8 24 was erroneously written on the heliogravure by the
keeper of the Chalon museum, Chevrier, instead of 1826, and this
mistake was carried over into the collection of the Conservatoire des
Arts et Metiers, as well as into the collection of the Paris photographic
society. Fouque established the date 1826 as correct (see Bull. Soc.
frang. d. phot., Sept. 1919, 3d ser., VI, 299-302).

We learn from a communication of his son Isidore Niepce 11 the
method used by his father at that time; it was a solution of asphalt in
Dippel’s animal oil 1 - with which the pewter plate was coated, fixed by a
“solvent” and then etched. Niepce sent this plate to Lemaitre, a clever
Parisian engraver, to be re-engraved (deepened by hand beyond the

JOSEPH NICEPHORE NIEPCE 205

depth attained by etching). This is undoubtedly the oldest photo-
graphic reproduction (heliogravure), and it was afterwards presented
by Nicephore Niepce’s son Isidore to the Chalon museum. It was ex-
hibited at the Paris Exposition in 1900 and is reproduced in the report
of the Exhibition Committee. 13

On January 1, 1827, Niepce sent to Lemaitre two copper plates,
prepared for etching, and shortly afterward five pewter plates slightly
etched with acetic acid. He writes that he is busy producing gravures
directly in the camera.

Regarding the use of pewter plates F. Paul Liesegang reports as fol-
lows: On May 26, 1826 (Fouque, p. 122), Niepce wrote to his son: “I
have just received new pewter plates. This metal lends itself better to
my purpose, especially for exposures from nature, since it reflects the
light strongly, and the image appears sharper. I congratulate myself on
this idea.” The use of pewter plates was at this time evidently something
new. This is important for the fixation of the dates of Niepce’s work.
His work on pewter plates cannot antedate 1826.

On January 17, 1827 (Fouque, p. 124), Niepce wrote to Lemaitre
in Paris, who did etching for him, that he had sent him two copper
plates to etch eighteen months previously, that is, in the middle of 1825.
Niepce was not adept at etching, as he states in his “Memoire” written
in England (Fouque, p. 149).

February 2, 1827, he sent Lemaitre five pewter plates for etching;
among the subjects were the Holy Family, a landscape, and a portrait.
Lemaitre inquired in his reply of February 7, 1827 (Fouque, p. 128),
why Niepce changed from copper plates, and he was told that pewter
was not so well adapted for this work. He returned the five plates
which he had worked upon March 5 together with proofs, and wrote
that they had “turned out” better than he had expected.

On March 17, 1827, Niepce requested Lemaitre to send him six or
eight proofs of copper engravings on thin paper, which he intended
to use in his experiments with copying. He received them March 28,
1827.

Meantime Claude, who resided in London, fell ill, and Niepce
traveled to London via Paris. He remained in Paris for a few days and
visited (1827) not only Daguerre but also Lemaitre. At this period he
speaks enthusiastically of Daguerre’s diorama and writes to his son
Isidore on September 4, 1827, that Daguerre caught the images in the
camera obscura on a phosphorescent substance, “which substance

206 JOSEPH NICEPHORE NIEPCE

eagerly absorbs light, but cannot retain it long.”

NICEPHORE NIEPCE EXHIBITS ASPHALTUM PHOTOGRAPHS ON
SILVERED PLATES IN ENGLAND IN I 827

When he arrived in London Nicephore found his brother Claude
seriously ill. On a chance visit to Kew he made the acquaintance of
Francis Bauer, who was secretary to the Royal Society of London,
and Niepce wanted him to submit to the Royal Society a “Memoire”
on his methods accompanied by proofs. This “Memoire,” dated at Kew,
December 8, 1827, was, however, never printed in the proceedings of
the society, since the method was not disclosed, and the society there-
fore declined to listen to the lecture on the invention. We leam of it
first through Fouque, who published the “Memoire” elsewhere.

Niepce then attempted to send, through Mr. Aiton, proofs of his
process to the king, but with no more success. He lived not far from
Kew, and during his stay he produced a picture of a church in Kew,
which has since disappeared.

Here must be noted that in the “Memoire” which Niepce wrote in
England he calls attention to the shortcomings of images on pewter
plates, that is, weakness of tone and poor contrast; he believed that he
could get a better effect with highly polished silvered plates (Fouque,
p. 149); which shows that at that time he had not yet used silvered
plates (F. Paul Liesegang) .

The first mention of his work on silvered plates is contained in his
letter to Lemaitre, August 20, 1828 (Fouque, p. 1 5 3 ). He writes there
of the resumption of his work after his return from England, which
was delayed by the nondelivery of silvered plates which he had
ordered. On October 4, 1828, he wrote to Lemaitre that he had sent
an image on a silvered plate to Daguerre (F ouque, p. 153); Daguerre
later speaks of this as an asphaltum image.

During his sojourn in England (1827) Niepce gave a Mr. Cussel
at Kew one of his prints. The latter wrote on the back of the picture:
“This prototype (undoubtedly erroneously meant for “phototype”)
was given me at Kew, in 1827, by Mr. Niepce, to whom we owe the
invention of this art.” As late as the end of the fifties Joseph Ellis, at
Brighton, saw the print in the hands of Cussel, and he desired to acquire
it. Cussel refused to part with it, because he himself placed a high value
on its possession. After this Ellis never lost sight of the picture, and
after Cussel’s death, about the beginning of the sixties, and the sale of

NIEPCE AND DAGUERRE 207

his property, he started a search for it and found the picture in the
hands of a second-hand dealer who thought it was a silvered plate. He
scratched off the back to convince himself of that and so acertained
that the metal was pewter, not silver, which circumstance alone is
probably the reason why this specimen, so historically important, did
not meet destruction in the melting pot of a smelter. Ellis bought the
picture and preserved it with care. It was an asphaltum-coated pewter
plate produced in a camera obscura and the reproduction of an engrav-
ing {Phot. News, July n, 1862, VI, 336; Horn’s Phot. Jour., XIX, 4).

The Museum of the Royal Photographic Society, London, acquired,
in 1924, three original plates by Niepce showing experiments in mak-
ing light images by the aid of light-sensitive asphaltum coatings, which
Niepce brought to London in 1827 on the occasion of his proposed
lecture before the Royal Society, and presented to F. Bauer the secre-
tary of the society; they passed into the possession of H. P. Robinson,
and finally his son, Ralph W. Robinson, presented these rare objects
to the above-mentioned museum, which is rich in historical documents.
These plates represent: the often-cited portrait of Cardinal d’Amboise,
originating from 1827, size 13.5 X 16.5 cm. (5.3 X 6.5 inches) ; Christ
carrying the Cross, from 1826, the picture short of 7.5 X 10 cm. (3 X
4 inches) on a plate 13 X 19 cm. (5.1 X 7.5 inches); a landscape (re-
production) dated 1827, plate 12X15 cm. (4.7 X 6 inches). There
was no exposure from nature among them.

Nicephore returned to France in January, 1828; Claude died at Kew
Green on February 10 of that year. 14

Chapter XX. relationship between niepce

AND DAGUERRE

Colonel Niepce, a cousin of Nicephore Niepce, on January 12,
1826, visited the celebrated opticians Vincent and Charles Chevalier
of Paris to buy optical equipment, particularly a camera obscura
equipped with a “prisme menisque” 1 which Niepce had asked him
to purchase. This “prisme menisque” was a meniscus lens invented by
the Chevaliers. It was of glass, ground concave on one side and convex
on the other. In the course of the conversation the colonel mentioned
that his cousin Nicephore was occupied with experiments leading to

208 NIEPCE AND DAGUERRE

the fixation of images produced by the camera obscura, and he showed
them a proof of a heliogravure made by Niepce, which surprised them.
In reply Charles Chevalier told him that a painter by the name of
Daguerre, in Paris, was at that time working along the same lines,
with the same purpose.

The famous opticians at the time of Niepce and Daguerre were
Jacques Louis Vincent Chevalier (1770-1840) and his son Charles
Louis Chevalier (1804-59), who especially devoted himself to the de-
velopment of photographic optics in Daguerre’s time. Charles Louis
Chevalier wrote on the camera obscura ( 1 8 2 9 ) , on microscopes (1839),
and Sur une modification apporte au doublet de Wollaston (1841),
Nouvelles instructions sur l' usage du daguerreotype (1841), Melanges
photo graphiques (1844), Sur quelques modifications apportees a des
instruments optiques (1841), and also other articles on microscopes.
He also wrote Photographie sur papier, verre et metal (1856), Me-
thodes photo graphiques perfectionnees (1859). The third generation
of the Chevalier family, Louis Marie Arthur Chevalier ( 1 8 30-7 2 ) , con-
tinued the business, having become associated with his father in 1848.
He wrote Methode des portraits des grandeur naturelle et des agrand-
issements photo graphiques (1862) and other articles on the subject.

Now a very curious incident happened, which Arthur Chevalier
relates in his work Etude sur la vie et les travaux scientifiques de Charles
Chevalier (Paris, 1862). A few days after the visit of Colonel Niepce
an unknown young man called at the place of business of the opticians
Chevalier and bought a cheap camera obscura, remarking, “I am sorry
that my means do not permit me to buy a better camera equipped with
a lens (appareil a prisme), for with such a one I might hope to fix the
image on the ground glass of the camera better.” At the same time he
showed positive images on paper, which he stated were produced by
the action of light. Later he brought to Chevalier a small bottle con-
taining a brown liquid which he claimed was sensitive to light. Chevalier
was unable to obtain a result with it, neither could Daguerre, whom
Chevalier told of it; they awaited the return of the stranger without
result— he never came back.

This incident led Chevalier to speak to Daguerre of Nicephore
Niepce’s experiments with heliography. He gave Daguerre Niepce’s
address and advised him to communicate with him. At first Daguerre
rejected this proposal, but he changed his mind and wrote a few days
later, about the end of January, 1826.

Chapter XXL the life of daguerre

Louis Jacques Mande Daguerre was born November 1 8 , 1787, at
Cormeilles-en-Parisis, France. 1 His father was a court attendant there, 2
but he moved to Orleans as an official of the royal government domain.
Young Daguerre, who showed a talent for drawing, entered, when
sixteen years old, the studio of the well-known scene painter Degotti.
He there attained great proficiency in perspective and lighting and
later collaborated with Prevost on many panoramic paintings in Rome,
Naples, and elsewhere.

As an artist Daguerre showed astonishing ingenuity in the handling
of light and lighting effects, and he supplied the scenic and lighting
effects for a number of operas on the stages of Paris theaters. About
1820 he conceived the idea of improving the panorama (devised by
the German Breysing and executed by Robert Barker, of Edinburgh,
about 1793), realizing it in his invention of the “diorama,” a variety
of the panorama, which might be called the precursor of the modern
picture theater. The first one shown in Paris was built by the American
engineer Robert Fulton, 3 in 1804, and drew great audiences. In 1822
Daguerre associated himself with the painter Bouton in the construc-
tion of an improved panorama, which he called “Diorama.” He opened
it on July 1 1, 1822, at 4 Rue de Sanson, in a spacious showroom. A
garden and main building on the adjoining corner of the Rue de Marais
were connected with this establishment. Here Bouton lived, and later
Daguerre, who conducted the business. The house was plain and in-
cluded a studio. Today the barracks of the Garde Republicaine occupy
the comer of the Rue de Marais, 4 and a tablet commemorating the
discovery of photography by Niepce and Daguerre, affixed to the wall
of the building, recalls its historic interest.

In addition to Bouton and Daguerre, other artists worked on the
diorama, Hippolyte Sebron and Charles Arrowsmith (both pupils of
Daguerre). Daguerre married Arrowsmith’s sister.

Potonniee, in the Bull. Soc. frang. de phot. (April, 1920, 3d ser., VII,
80-85), cites a hst °f the changing pictures, ( tableaux change ants)
shown in the diorama.

The diorama was one of the main attractions of the city and achieved
great popularity. The ticket of admission to the diorama for the year
1836 which was presented by Dr. O. Prelinger of Berlin, through Dr.
Eder, to the collection of the Graphische Lehr- und Versuchsanstalt,
Vienna, was first published in the Phot. Korr. (1918, LV, 309). It

2 10

THE LIFE OF DAGUERRE

shows that the diorama was open between 1 1 a.m. and 4 p.m. and that
the price of admission was one franc, a considerable fee for those days.
Of interest are Daguerre’s autograph and the validity of the ticket for
only a limited period.

One of the scenes of the diorama showed a catastrophe which oc-
curred at Goldau, in the Swiss canton Schwyz, where in 1 806 a tre-
mendous landslide buried several villages and filled part of the Lowerzer
Lake. Daguerre reproduced this in a painting, showing the rural scenery
with artificial lighting effects. Another picture showed a midnight mass
at the Church of St. Etienne du Mont, Paris. The interior of the
church appeared at first in daylight, and gradually, by means of light-
ing effects from the rear, it “dissolved” to an evening view, passing
eventually to a scene showing the midnight mass.'

Although at this time he was already quite busy with his experiments
on the production of light images, he carried on the business affairs of
the diorama. The original of the following letter of Daguerre, written
in 1830, is in the collection of the Vienna Photographic Society.

Paris, July 1, 1830

My dear Mr. Dauptain:

Being unable yesterday to pay the last note of 548 francs, I called on
Messrs. Camus and Cotu and requested them to give me until tomorrow,
Friday, which they will gladly do on a word from you. Will you oblige
me and give it to bearer.

Yours very devotedly,

^Signed] Daguerre

Messrs. Camus and Cotu, Rue des Arcis, No. 17.

It appears from this letter that Daguerre at that period was sometimes
pressed for money, although he was considered well-to-do. His income
from the diorama and from his painting incident to it furnished
Daguerre with the means for his photographic experiments. The dio-
rama continued to prosper until 1839, when a fire caused by the care-
lessness of a machinist destroyed the building and its interior fittings,
including all his early works. The building was later reconstructed
nearby by Bouton ( 1842-43) , but Daguerre was no longer interested in
it. An illustration of an exhibition in Daguerre’s diorama in 1822 may
be found in Tissandier’s Les Merveilles de la photographic (Paris, 1874,
p. 2 1 ) .

The esteem in which Daguerre’s diorama and his paintings were held
is attested by the honor bestowed upon him in his appointment in 1824

THE LIFE OF DAGUERRE 21 1

as Chevalier of the Legion of Honor; in 1839 he became Officer of the
Legion.

Daguerre’s diorama consisted of paintings in which the change from
daylight to evening light was realistically imitated; in some cases figures
appeared and disappeared. The effects were produced by painting the
picture on both sides of the thin linen, which was lighted now from
the front and then from the back. The onlookers therefore saw the
picture of the same subject under changed conditions; for instance,
Vesuvius was shown in day by light concentrated upon it, and as seen
at night by dim effects of light penetrating from behind.

daguerre’s works of art

We cannot go into detail here concerning the numerous paintings
and the small number of lithographs, and so forth, by Daguerre. The
Bull. Soc. frang. d. phot. (1894, 2 ser., X, 590-93) contains a gravure
reproduction of one of his paintings.

Another well-preserved panoramic painting by Daguerre is found
in the church at Bry-sur-Marne, the little town to which Daguerre
retired after disposing of his invention in 1839. We owe this to the
initiative of Mile de Rigny, who lived in Bry at that time. This learned
lady, who died at the age of 82 in her castle at Bry, in 1857, studied
science and astronomy with Laplace and Bouvard. She induced Da-
guerre to paint a picture for the interior of the church. In order to find
a place for it, she had built at her own expense an annex behind the
altar. Daguerre worked diligently for six months, often fifteen hours
a day, on this picture, which represents the nave of a Gothic cathedral
and recalls the perspective effects of his diorama. 6

THE DIORAMA AS SEEN BY HIS CONTEMPORARIES

It is interesting to read a view of a contemporary of Daguerre’s
picture show. August Lewald (1792-1871), German author and actor,
who traveled a great deal, visited Daguerre at his Paris diorama in 1832,
then called “Salle de miracle,” and described his experience in his
Gesammelte Schriften (Leipzig, 1845, p. 348). Dr. O. Prelinger called
the attention of the present author to the publication. The chapter
reads as follows:

A Breakfast at Daguerre's

We sat in a pleasant circle in the house of a friend at Neuilly. It was a
beautiful evening; we inhaled the air perfumed by thousands of blossoms,

2 I 2

THE LIFE OF DAGUERRE

filling our lungs and giving us a feeling of infinite pleasure. Since we were
in happy mood, our conversation was enlivened by friendly jests. A
beautiful young English lady, who was leaving in a few days for Geneva
and Chamonix and in whom I became interested, seemed to be the only
one who did not take part in the entertainment. Jokes of all kinds were
not scarce, but although they were kept within the strict limits, the young
lady did not appear to enjoy them. I noticed her ill humor, winked at my
host, and we left her severely alone.

After a while she told us, without being asked, the cause of her dejection.
She came from one of the romantic sections of her country, where verdant
hills change into rocky scenes, seeming like the work of an artist. She re-
called the quiet solitude, comparing it with the noise and the hustle of the
city and even of the countryside, and this produced the melancholy sadness
in her.

“And do you suppose that you cannot find again right here your moun-
tains, your rural scenes, in short, everything which you miss so sorrow-
fully?” I asked.

The author, Lewald, then relates how the small company went to
Daguerre’s diorama.

Here was no theater, no wings, we found ourselves under the eaves of
a Swiss peasant’s home. Farm tools were strewn about here and there; it
looked as if our unannounced arrival had scared away the bashful tenants.
Below us we saw a small courtyard surrounded by buildings. On our right
an open window from which hung some clothes for drying; there was a
sawhorse and an axe and some wood that had been cut lay about under the
stable doors; at our left a goat bleated, and not far away the melodious
bells of the herd faintly sounded.

But a little farther on, what a view! The valley, covered with snow, was
protected by the mountain giants. There could be no further question of
what we saw before us. I extended my hands and explained that before us
was Chamonix, more than three thousand feet above sea level; at our left
Montanvert, lifting his white head above the green night of the fir forests;
in the middle of the valley the majestic hump of the Dromedar, that highest
point of the Mont Blanc group, 14,700 feet high; on the right, still hidden
by the clouds, the Dom du Gouter; below Mont Blanc the glorious Bosson
glacier, whose icy foot is rooted in the valley itself; and not far away the
Breven. On the left the giant granite needles reach up to the dark sky,
and in the center the Arveyron gurgled its way through ice and snow.
Beaten paths showed in the snow, a few houses slumbered peacefully sur-
rounded by grave firs covered with snow.

“It is April,” I concluded, “which, of course, is warmer here than there.

THE LIFE OF DAGUERRE

2 1 3

We can transcend space, but it is not within the power of man to drive
forward the wheels of time. A month later, and this lovely valley would
have presented itself more pleasantly in the finery of its green meadows.”

Everyone stood still with astonishment, but one surprise follows another.

Behind us wooden plates, spoons, and glasses clattered. We turned around
and saw a young girl in the costume of the mountain folks serving a country
breakfast consisting of milk, cheese, dark bread, and sausage, while a foot-
man poured Madeira, port wine, and champagne into crystal glasses.

“I am enchanted!” said the young woman, pressing my hand as I escorted
her to the nicely arranged table.

We were seated at breakfast when the Alpine horns sounded a short
festival ritomello, after which a strong male voice in the valley sang a
national song “The Chamois Hunter” in the dialect of the Chamonix
Valley.

We were all wonderfully touched; the young lady had tears in her eyes.

“That cannot be painting, so far your magic cannot extend,” she said
finally; “there is here an extraordinary combination of art and nature,
producing an overwhelming effect, and one is unable to discern where
nature ceases and human skill begins. That house is built, those trees are
natural, and further— yes, further,” she said hesitatingly, “one is lost.
Where is the artist who created this?”

“My friend Daguerre,” I exclaimed enthusiastically, “long may he live!”

All clinked their glasses and Daguerre approached, thanked them, and
expressed his pleasure at having been able to give them this pleasurable
surprise in his diorama.

“Many art critics wanted to indict me for the crime of mixing art and
nature; they say that my live goat, my real pines, and the peasant’s hut are
artifices prohibited to the painter. Be that as it may! My only aim was
to effect illusion at its greatest height; I wanted to rob nature, and it was
therefore necessary to become a thief. If you visit Chamonix, you will find
everything substantiated; the hut, these eaves, and all the stage properties
you see here, even the goat down there I imported from Chamonix.”

“Then it is the diorama I am visiting?” asked the young lady.

“Yes.”

“But the singers; the breakfast?”

“We are in Paris. Our boulevards furnish dancers, singers, costumes,
and breakfasts according to the taste of all nations.”

“Extraordinary! This kind of surprise can only be achieved in Paris.”

“And a breakfast like this could only be served by Daguerre, the greatest
living artist in his class. Let us ascend the stairs and admire the smaller
paintings of the diorama.”

We were standing under a gorgeous cupola, and the platform on which

THE LIFE OF DAGUERRE

214

we stood revolved. There passed before our enchanted eyes glorious Edin-
burgh, illuminated by a fire, and the tomb of Napoleon at sunset.

August Lewald added the note that this was written as early as 1832,
when no one knew that Daguerre was busy with photographic experi-
ments or dreamed that he was to be so great an inventor.

SPREAD OF THE DIORAMA TO OTHER COUNTRIES

Bouton went to London in 1832, painted several pictures for dio-
ramas in England, and shipped some of them to America. He returned
to Paris after the destruction of Daguerre’s diorama (1839) and built
a new show place in the neighborhood (1842-43).

In Germany the diorama found its first home in Breslau, but the only
important one, modeled after the Paris diorama, was built at Berlin in
1826 by Carl Gropius, who learned personally from Daguerre the de-
tails of construction and equipment. It continued its operations until
the fifties and then succumbed, like its Paris predecessor, with all its
painted scenery, to a conflagration.

Erich Stenger has reported on this in his booklet Daguerre's Diorama
in Berlin; ein Beitrag zur Vorgeschichte der Pbotograpbie (Berlin,
Union deutsche Verlagsanstalt, 1925). This is written with a great
deal of technical knowledge and shows intensive research.

Without going into details of the later popularization of the diorama,
we must mention a Swedish diorama on which Helmer Backstrom, in
Nord. Tidskr. f. Fot. (1920, IV, 17), reports: “In the autumn of 1843
a small diorama painted by C. A. Dahlstrom opened in Stockholm; in
1846 the decorative painter of the Royal Opera House, G. A. Muller,
started a new diorama, soon followed by other installations.”

daguerre’s studies of physics, his experiments with the camera

OBSCURA, AND HIS CONTRACT WITH NIEPCE FOR JOINT WORK (1829)

Along with his artistic labors, Daguerre constantly applied himself
to his physical studies, especially concerning light and its action.
However, at that time he seemed to have experimented only with
phosphorescent substances, and his studies covered mainly the camera
obscura. His improvement of the camera obscura consisted in causing
Chevalier to improve the periscopic lens by achromatizing it, a lens
which had been introduced by Wollaston (1812). The well-known
optician, Charles Chevalier, at the Palais Royal, in Paris, furnished the
optical accessories. We have already mentioned how Chevalier offered

AGREEMENT BETWEEN NIEPCE AND DAGUERRE 2 1 5

an opportunity for the coming together by correspondence and in
person of Daguerre and Niepce.

At first their relations were very constrained, owing to the mutual
reluctance to divulge too much concerning the results each had
achieved. Nicephore Niepce brought the matter to a head in 1829 by
accepting Daguerre’s offer to join him in the further improvement of
the heliographic processes.

Chapter XXII. the agreement between

NICEPHORE NIEPCE AND DAGUERRE (1829)

On December 14, 1 829, a contract was drawn up by a notary between
Nicephore Niepce and Daguerre. The latter came specially to Chalon
for this purpose. The first paragraph of the agreement signed by them
stated: “Between Niepce and Daguerre, formed to co-operate for the
further improvement of the invention of Niepce which was perfected
by Daguerre.”

Owing to the historic importance of this contract, we give here a
literal translation of the original:

Basis of the Preliminary Agreement

between the undersigned M. Joseph Nicephore Niepce, landowner, resid-
ing at Chalon-sur-Saone, Department Saone-et-Loire, party of the first
part, and M. Louis Jacques Mande Daguerre, artist-painter, member of
the Legion of Honor, Director of the Diorama, residing at Paris at the
Diorama, party of the second part, who propose to establish a company
planned by them, have set down the following preliminaries, to wit:

M. Niepce, in his endeavor to fix the images which nature offers, without
assistance of a draughtsman, has made investigations, the results of which
are presented by numerous proofs which will substantiate the invention.
This invention consists in the automatic reproduction of the image received
by the camera obscura.

M. Daguerre, to whom he disclosed his invention, fully realizing its
value, since the invention is capable of great perfection, offers to join with
M. Niepce to achieve this perfection and to gain all possible advantages
from this new industry.

According to this arrangement the contracting parties have set down
their agreement to the preliminary and basic articles in the following
manner:

216 AGREEMENT BETWEEN NIEPCE AND DAGUERRE

Art. i. Under the name of the firm Niepce-Daguerre a company is
founded between Messrs. Niepce and Daguerre for the joint work on the
further perfection of the above mentioned invention made by M. Niepce
and perfected by M. Daguerre.

Art. 2. The term of this contract is to be fixed for ten years from
December 14 of the present year; the partnership cannot be dissolved
before the end of this term without the mutual consent of the interested
parties. In the case of death of one of the associates his assignee takes his
place for the unexpired period of the ten years; further, in the case of death
of either partner, the above-mentioned invention may only be signed by
the two names designated in Art. 1.

Art. 3. Immediately following execution of this contract M. Niepce
must communicate to M. Daguerre, under the seal of secrecy, which is to
be protected by a penalty covering costs, damages, and interest, the prin-
ciple on which his invention is based and to place at his disposal the exact
and fully detailed documents on the nature, the use, and the different ways
of manipulation which are referred to in order that by complete co-opera-
tion the research and experiments may be directed to the perfection and
exploitation of the invention.

Art. 4. M. Daguerre binds himself at the risk of the above-mentioned
penalty to preserve absolute secrecy, not only in regard to the basic prin-
ciple of the invention but also regarding the nature, application, and use of
the processes which will be communicated to him, and in addition to co-
operate as much as possible in the improvements deemed necessary, con-
tributing his knowledge and talents.

Art. j. M. Niepce contributes to the company and transfers to it his
invention, which represents the value of half of the returns capable of
attainment, and M. Daguerre contributes a new design for the camera
obscura, his talents, and his ability, which are considered equal to the other
half of the returns mentioned.

Art. 6. Immediately following the execution of this contract M. Da-
guerre must communicate to M. Niepce under the seal of secrecy, which
is to be protected by a penalty covering costs, damages, and interest, the
principle on which the improvement is based which he has added to the
camera obscura and is to place at his disposal the most fully detailed docu-
ments describing the nature of the improvement mentioned.

Art. 7. Messrs. Niepce and Daguerre are each to contribute one half
of the cash capital necessary for the starting of the business.

Art. 8. If the partners deem it appropriate to apply the above-mentioned
invention to practical use by the process of engraving, i. e., to employ the
advantages which may arise for the use of the above-mentioned process
by an engraver, Messrs. Niepce and Daguerre pledge themselves to choose

AGREEMENT BETWEEN NIEPCE AND DAGUERRE 2 1 7

no other person but M. Lemaitre for the execution of the mentioned use.

Art. y. On the execution of the final agreement the partners nominate
from among themselves the director and the treasurer of the company,
which has its place of business in Paris. The duty of the director is to
manage the enterprises stipulated by the partners, and that of the treasurer
to collect the outstanding debts assigned to him by the director for the
benefit of the company and to settle all bills payable.

Art. to. The term of service of the director and the treasurer run for
the term of the present contract. Re-election is permissible. A compensa-
tion for their services cannot be demanded by either the director or the
treasurer, but there may be allowed to them a participation in the profits
as compensation, if it is so agreed at the time of execution of the final
contract.

Art. 11. The treasurer is to submit to the director every month his ac-
counts and the trial balance of the company, and the profit is to be divided
every half year among the partners in the manner stipulated below.

Art. 12. The accounts of the treasurer and the trial balance are to be
examined, ratified, and discharged semiannually by the partners.

Art. 13. The improvements and perfections to the above-mentioned
invention, as well as those added to the camera obscura, are and remain
the property of both partners who, when they have attained the object
which they desire, will execute a final contract on the basis of the present
agreement.

Art. 14. Half the profits of the company from the net proceeds of the
company are to be paid to M. Niepce as inventor, and half to M. Daguerre
for his improvements.

Art. 13. All controversies which may arise between the partners from
this present agreement are to be decided finally, without recourse to the
courts, by arbitrators who are to be called in by both sides in friendly
agreement, according to Art. 51 of the Code of Commerce.

Art. 16. In case of the dissolution of the company, the liquidation is to
be executed by the treasurer, by mutual agreement, or by both partners
together, or finally by a third person on whom they agree, or who is
appointed by the competent tribunal on the application of the partner in
charge of the business affairs.

Approved and attested

[Signed] J. N. Niepce

Approved and attested

[Signed] Daguerre

Recorded in the Register at Chalon-sur-Saone, March 1 3, 1 8 30. f . 3 2 V. C.
9 and ff. Received 5 fcs. 50 ctms., including the tax.

[Signed] Decordeaux

2 1 8 AGREEMENT BETWEEN NIEPCE AND DAGUERRE

The signatures and acknowledgment to this important agreement
are reproduced in facsimile by a line etching which shows the auto-
graphs of Niepce and Daguerre in Eder’s Geschichte der Pbotographie
(4th ed., 1932, p. 282).

In Article 3 of the contract Niepce is pledged to describe exactly
the principle underlying his invention. Since this document has been
preserved to us, we know that Niepce was perfectly familiar with the
heliographic asphalt process.

This “Notice sur l’heliographie,” by Nicephore Niepce, written
as a supplement to the above agreement in 1829, was published by
Daguerre himself in his Historique et description des procedes du da-
guerreotype et du diorama (Paris, 1839). Fouque also prints this in his
book. Niepce writes:

The invention which I made and to which I gave the name “heliography”
consists in the automatic reproduction, by the action of light, with their
gradations of tones from black to white, of the images obtained in the
camera obscura.

Basic Conception of This Invention

Light in the state of combination or decomposition reacts chemically
on various substances. It is absorbed by them, combines with them, and
imparts to them new properties. It augments the natural density of some
substances, it even solidifies them and renders them more or less insoluble,
according to the duration or intensity of its action. This is, in a few words,
the basis of the invention.

First Substance: Preparation

The first substance which I use, the one which makes my process most
successful and which contributes more directly to the production of the
effect, is asphaltum, or the so-called bitumin (pitch) of Judea, which is
prepared in the following manner:

I fill half a glass with this pulverized pitch and then pour, drop by drop,
lavender oil on it until the pitch will absorb no more and is entirely satu-
rated with it. Then I pour more of this essential oil on it until it stands three
“lignes” 1 above the mixture, which is then covered and set in a place of
moderate temperature until the oil is saturated by the coloring matter of
the pitch. If this varnish is not of the proper consistency, it is allowed to
evaporate in a dish, protecting it against moisture which would modify
and finally disintegrate it. This unfortunate result is particularly to be
guarded against in the camera during the cold damp season. 2

AGREEMENT BETWEEN NIEPCE AND DAGUERRE 2 1 9

If a highly polished metal plate plated with silver is coated with a small
amount of this cold varnish, using a very soft leather ball, it gives the
plate a beautiful red color and spreads over it in a very thin uniform coat-
ing. Then the plate is placed on a hot table which is covered over with
several layers of paper, from which the moisture previously has been re-
moved, and when the varnish is no longer tacky, the plate is withdrawn to
allow it to cool and permit it to dry completely in a moderate temperature,
protected from the influence of the moisture in the air. I must not forget
to mention that this precaution is indispensable principally when the var-
nish is applied. In this case, however, a thin disk is sufficient, in the center
of which a short peg is fixed, which is held in the mouth to keep away the
moisture of the breath and condense it.

A plate prepared in this manner may be exposed immediately to the
action of light; but even after prolonged exposure nothing indicates that an
image really exists because the impression remains imperceptible.

It is therefore a question of developing the picture, and this can only be
accomplished by the aid of a solvent.

Preparation of the Developer

Since the developer must be regulated according to the result that is to
be obtained, it is difficult to determine the proportions of its composition
with exactness; but all things being equal, it is desirable that it be a little
weak rather than too strong; that which I prefer consists of one part
lavender oil and six parts of white mineral oil or petroleum. The mixture,
which at first is quite milky, becomes perfectly clear after two or three
days. It can be used several times in succession, losing its solvent property
only when it approaches the saturation point, which is indicated by the
liquid’s becoming turbid and dark in color; but it may be distilled and
made as good as before.

When the plate or varnished tablet is taken out of the camera, it is
placed in a white metal dish an inch deep, and longer and wider than the
plate, and a plentiful quantity of this developer is poured in it, covering
the plate entirely. When the plate is observed under an oblique light at a
certain angle, the image can be seen to make its appearance, slowly and
gradually developing, although still darkened by the oil which, saturated
more or less with varnish, flows over it. The plate is then taken from the
liquid and placed in a perpendicular position, in order that it may be
entirely drained of all developer, after which we proceed to the last opera-
tion, which is no less important.

Washing the Plate

A very simple arrangement is required, consisting of a board four feet
long and a little wider than the plate. Two strips are nailed on lengthwise,

220 AGREEMENT BETWEEN NIEPCE AND DAGUERRE

which form a border two inches high. On top is a hinged handle which
makes it possible to move the board up and down in order to give the
water which is poured on it the required speed. At the bottom is a vessel
which receives the liquid flowing off.

The plate is placed on the inclined board and is kept from sliding off
by two small nails or hooks, which, however, must not protrude above the
face of the plate. At this time of the year (winter) it must be remembered
to use lukewarm water. The water is not to be poured upon the plate
itself, but on the board, somewhat above the plate in order to obtain a fall
sufficient to carry away the last of the oil adhering to the varnish.

The picture is now fully developed and appears perfectly and completely
defined if the operation has been successful, especially if one has a perfect
camera obscura at one’s service . 3

Uses of the Heliographic Process

Since the varnish can be used with equal success on stone, metal, and
glass without necessitating any change of procedure, I shall confine myself
to the method of application to silvered plates and glass, calling attention
once for all to the fact that in printing on copper a little wax, dissolved
in lavender oil, may be added to the varnish mixture without damage . 4

Until now silvered plates seem to me best suited for the production of
pictures, owing to their white color and their nature. It is certain that
after washing, assuming that the image is quite dry, the result is satisfactory.
It would be desirable, however, to obtain all gradations of tone from black
to white by blackening the plate. I therefore occupied myself with this
subject, using at first a solution of potassium sulphide (sulfure de potasse);
but if a concentrated solution is used it attacks the varnish, and if diluted
with water it turns the metal red. This twofold defect compelled me to
give up this medium. The substance which I am now using with greater
expectation of success is iodine , 5 which has the property of evaporating
at ordinary temperatures. In order to blacken the plate by this method, it
is only necessary to place the plate against the inner side of a box that is
open at the top and to put a few grains of iodine into a groove cut into
the opposite side on the bottom of the box.

It is then covered with a glass, in order to observe the result, which,
although it shows less rapidly, is all the more certain in its effect. The
varnish can then be removed by alcohol, and not a trace will remain of
the original impression. Since this process is still quite new for me, I confine
myself to this simple description until experience has allowed me to collect
more precise details.

Two experiments showing views on glass exposed in the camera obscura
have furnished me with results which, although still faulty, seem to me

AGREEMENT BETWEEN NIEPCE AND DAGUERRE 221

quite remarkable, because this mode of application can be more easily
perfected and therefore may become of special interest.

In one of these experiments the light, which had acted with less intensity,
had dissolved the varnish in such a manner that the gradations of tones
showed more clearly when viewed by “transmission” (i. e., transmitted
light), so that the picture reproduced, up to a certain point, the well-known
effects of the diorama.

In the other experiment, however, where the action of the light was
more intense, the lightest parts, which were not affected by the developer,
remained transparent and the gradations of the tones depended entirely
and solely on the density of the more or less dark layers of the varnish. If
the image is viewed on its varnished side by reflection in a mirror, and held
at a certain angle, the effect is greatly enhanced, while if viewed by trans-
mitted light, it appears confused and colorless, and, what is still more re-
markable, it seemed to differentiate the separate tones of certain objects.
When I considered this curious phenomenon, I believed that I might draw
certain conclusions from it, which permitted a connection with Newton’s
theory of colored rings. It would be sufficient to assume that any prismatic
ray, the green for instance, in acting on the substance of the varnish and
combining with it, gave it the necessary degree of solubility, so that after
the double operation of the developer and the rinsing, the layer which had
formed by this method would reflect the green color. Whether this hy-
pothesis is well founded is a matter for future investigation, but the subject
seems to me of itself so interesting that it may well deserve further ex-
periments and more exact proof.

Remarks

Although the application of the necessary media described above un-
doubtedly offers no difficulty, it may happen (when the procedure is not
carefully followed) that in the beginning the operation will not turn out
well. I believe, therefore, that it is advisable to start in a small way by copy-
ing copper engravings in diffused light according to the following very
simple method. Varnish the engraving only on the reverse side to make it
thoroughly transparent. When the paper is completely dry, place it face
down on the coated plate under a glass, the pressure being modified by
inclining the plate at an angle of 45 degrees. By this method it is possible to
make several experiments in the course of a day, using two engravings
properly prepared and four small silvered plates. This can be done even in
overcast weather, providing that the workroom is protected against cold
and especially against moisture, which, I repeat, deteriorates the varnish
to such an extent that it will float off in layers when the plate is immersed
in the developer. It is for this reason that I ceased using the camera obscura

222 AGREEMENT BETWEEN NIEPCE AND DAGUERRE

during the inclement season. If the experiments which I have described
are continued, one will soon be well able to carry out the details of the
whole process.

In the matter of applying the varnish, I must call attention again to the
fact that it can be used only in a consistency which is thick enough to
form a compact yet thin coating, in order that it might resist better the
action of the developer and become at the same time more sensitive to the
action of light.

In respect to the use of iodine for blackening the images produced on
silvered plates, as well as regarding the acid for etching the copper, it is
essential that the varnish after washing be used exactly as described above
in the second experiment on glass; because it becomes thus less permeable,
both in acid and under the iodine vapors, particularly in those parts where
it has retained full transparency, for only under these conditions can one
hope, even with the best apparatus, to obtain a completely successful result.

Additions

When the varnished plate is removed for drying, it must be carefully
protected not only from moisture but also from any exposure to light. In
speaking of my experiments in diffused light, I have not mentioned any
of these kinds of experiment on glass. I add this in order not to omit a
specific improvement which relates to them. It consists simply in placing
a piece of black paper under the glass and in putting between the metal
plate on its coated side and the copper engraving a border of cardboard on
which the engraving has been tightly stretched and glued. This arrange-
ment has the effect of making the image appear much more vivid than on a
white background, which helps to accelerate the action, and, furthermore,
of avoiding damaging the varnish by rubbing it against the copper en-
graving as in the other method, a mishap which is very hard to prevent in
warm weather, even when the coating is quite dry. This disadvantage is
counterbalanced, however, by the advantages offered by the experiments
with silvered plates, which withstand the action of the washing better,
while it is rare that the images on glass are not more or less damaged by this
operation, for the simple reason that the varnish can adhere less easily to
the glass, owing to its nature and its smooth surface. It would be necessary,
therefore, in order to overcome this disadvantage, to improve the varnish
by making it more sticky, and I believe that I have succeeded in doing this
at least in so far as I may be permitted to pass judgment on this matter,
although the experiments are still new and not numerous enough.

This new varnish is composed of a solution of bitumen of Judea in
Dippel’s animal oil, which is allowed to condense at the ordinary tem-
perature of air to the degree of consistency required. This varnish is more

IODIZED SILVERED PLATES

223

greasy, tougher, and more strongly colored than the other, and it can be
exposed to light as soon as the plate is coated, because it seems to solidify
more rapidly, owing to the great volatility of the animal oil which causes
it to dry more rapidly.

^Signed] J. N. Niepce

Issued in Duplicate
December 5, 1829

We call attention to the fact that as early as 1829 Niepce exposed
silvered metal plates to the fumes of iodine, although only for the pur-
pose of darkening the bare portions of the silver on which an asphalt
photograph existed, in order to reproduce the shadows of the image
more strongly; these light portions were formed in those places which
had been protected by the asphaltum made insoluble by light and from
which the asphaltum coating had been removed by more active sol-
vents.

This “Notice sur l’heliographie” of N. Niepce is the earliest exact
description of a photographic process. It is so elaborate that quite
satisfactory heliographic etchings can be produced by following the
directions. The production of pictures in the camera is of course
possible only after several hours’ exposure. The process is therefore
not practical for taking pictures from nature in the camera. It is worthy
of notice that Niepce acquainted Daguerre with his really new inven-
tion, but that Daguerre had no important photographic contribution
whatever to offer.

Chapter XXIII. daguerre discovers the

LIGHT-SENSITIVITY OF IODIZED SILVERED PLATES

Following the Agreement of December 14, 1829, both Niepce and
Daguerre worked assiduously on the improvement of the process. The
immediate problem was to find a light-sensitive material which would
give a more perfect light image with a shorter exposure than was
possible with the bitumen and other agents hitherto employed by
Niepce. By a “fortunate accident” Daguerre was led to the discovery
of the light-sensitivity of iodide of silver. 1 Louis Figuier, in his Exposi-
tion et bistoire des principal de convenes scientifiques modemes (I, 15),
relates the incident as follows: 2 “One day a silver spoon was by chance

IODIZED SILVERED PLATES

224

lying on an iodized silver plate and left its design on the plate by light
perfectly.” Observing this Daguerre wrote to Niepce, on May 21,

1831, suggesting the use of iodized silver plates as a means of obtaining
light images in the camera. It appears from the letters of Niepce to
Daguerre, dated June 24 and November 8, 1831, that Niepce was un-
successful in obtaining satisfactory results in following Daguerre’s
suggestion, although he had produced a negative on an iodized silver
plate in the camera.

It is also shown, in Niepce’s letters of January 29 and March 3,

1832, that the discovery and use of iodized silvered plates as a light-
sensitive material are due, not to Niepce, who did not use iodine as a
means of blackening certain parts of his light images, but to Daguerre.
Daguerre was thus the first to employ iodized silvered plates as the
light-sensitive coating by which he obtained pictures photographically.

The following anecdote appeared in 1906 in French periodicals.
The wife of a poor painter called one day on the celebrated French
chemist and member of the Academy of Sciences J. Dumas to ask
for his advice. “My husband,” she complained, “is about to lose his
reason. He has given up his art and carries on fruitless chemical experi-
ments. At present he has the obsession to retain images fixed on metal
plates. He has sold our possessions to buy chemicals and to build an
apparatus.” Dumas replied that he did not see what he could do in the
matter, and the lady explained her hopes that he, owing to his reputa-
tion as an authority on chemistry, could convince her husband of the
futility of his experiments. Dumas actually visited the painter the next
day. But it turned out contrary to the wife’s expectations, for after a
short conversaton with the painter-inventor he said: “Continue with
your experiments, and if you lack the funds I shall assist you myself.”
The painter was Daguerre, who a few years later completed his inven-
tion “of fixing images on polished metal plates” and presented to the
astonished world his “daguerreotype.” The story may be true; the cir-
cumstances tally with those of about 1831. J. Dumas himself related
this story in 1864, in a lecture before the Societe d’Encouragement
pour l’lndustrie Nationale. Dumas placed his laboratory at Daguerre’s
disposal at this time and gave him advice, which was undoubtedly of
great service, since Daguerre was not at all versed in chemistry.

Daguerre himself, as early as 1839, the year of the publication of
his process by the Paris academy, apprehended the doubts which might
later arise in regard to the identity of the person to whom the distinc-

IODIZED SILVERED PLATES

22 5

tion of the discovery of the light-sensitivity of iodized silver plates was
due. On this account he presented Niepce’s letters to him to the
academy in 1839, had them attested by Arago, and published that
year. Extracts from this correspondence are printed in many early
publications dealing with the process, also in English translations. 3

EXTRACTS FROM THE LETTERS OF NIEPCE TO DAGUERRE

St. Loup de Varennes, June 24, 1831

Dear Sir and valued associate:

I have awaited news from you with great impatience. I have now re-
ceived and read your letters of the 10th and the 2 1st of last month with the
greatest pleasure. For the present I confine myself to answer yours of the
2 1st because I have occupied myself since its receipt with your experiments
with iodine, and I hasten to report to you the results which I achieved. I had
dealt with this same experiment before having become associated with you,
but with no hope of success, because I considered it an almost impossible
matter to fix the exposed images in a lasting manner, even if we should
succeed in keeping light and shade in their proper arrangement. My ex-
periments along these lines had quite the same success which I obtained
with silver oxide, and the rapid action was the only real advantage which
these two substances seemed to offer. In the meantime I made new experi-
ments with iodine last year, after your departure from here, but according
to another procedure; after I had reported the results to you and received
your unsatisfactory reply I decided to discontinue my experiments. It
seems that you meanwhile regard this question from a more hopeful point
of view, and I have therefore no hesitation in granting your request ad-
dressed to me, etc.

[Signed] J. N. Niepce.

True copy:

Arago. Daguerre.

St. Loup de Varennes, Nov. 8, 1831.

Dear Sir and valued companion:

. . . Referring to my reply of June 24, 1831, to your letter of May 21,
I have made a great number of experiments with iodine in combination
with silvered plates, without at any time obtaining the results which the
deoxidation medium would have lead me to expect. Notwithstanding all
changes to which I subjected the procedure and all various combinations
of different methods of tests, my success was no more fortunate. I am now,
on my part, thoroughly convinced of the absolute impossibility of repro-
ducing negatives with light and shade effects in their natural sequence and
also, particularly, to attain anything more than a fugitive image of objects.

226 DEVELOPMENT WITH MERCURY VAPORS

At any rate, my dear Sir, this unsuccessful result is quite the same as those
which I obtained in my tests with metal oxides long ago and which induced
me to discontinue them. I finally decided to combine iodine with pewter, a
process which at the start seemed to promise a favorable result. I had made,
however, only once the astonishing observation during an experiment in
the camera that light acts on iodine in the reverse manner, i.e., that the
shades or, rather, light and shade, appear as in nature. I do not know how
and why this result happened, and I could not produce it again by a careful
repetition of the same procedure. However, this practice, as far as the
fixation of the image obtained is concerned, would be as inadequate as
before. After some other trials I remained at this point, and I must confess
that I am exceedingly sorry to have pursued for so long a time a wrong
direction, and what is worse, without any profit, etc.

^Signed] J. N. Niepce

True copy:

Arago. Daguerre.

Chapter XXIV. Joseph nicephore niepce’s

DEATH IN 1833; HIS SON ISIDORE TAKES HIS FA-
THER’S PLACE IN THE CONTRACT OF 1829 WITH
DAGUERRE; DAGUERRE DISCOVERS DEVELOP-
MENT WITH MERCURY VAPORS

Unfortunately Nicephore Niepce was taken from his labors as early
as July 5, 1 8 3 3 ; he died from apoplexy of the brain at his home in Gras,
near Chalon, without reaping the benefits of his efforts. In 1885 a
statue of Niepce, for which the funds were publicly subscribed, was
erected in front of his birthplace in Chalon. 1 His residence there is
adorned with a memorial tablet, and in the museum now occupying
his house are preserved the apparatus and earliest photographic proofs
of Niepce.

After Niepce’s death his son Isidore, as heir, took his place in the
contract with Daguerre, who thereafter carried forward the technical
work alone. However, in 1835 Daguerre insisted on an “addition” to
the first contract of 1829, in which he stated that his new process was
not based on the principle mentioned in that contract. The company

DEVELOPMENT WITH MERCURY VAPORS 227

changed its name by mutual consent; it was no longer Niepce-Da-
guerre, but was called “Daguerre et Isidore Niepce.”

Addition to Original Contract

Between the undersigned Louis Jacques Mande Daguerre, artist-painter,
member of the Legion of Honor, director of the diorama, residing at
Paris, and Jacques Marie Joseph Isidore Niepce, landowner residing at
Chalon-sur-Saone, son of the late M. Nicephore Niepce, sole heir, ac-
cording to Article 2 of the provisory agreement of December 14, 1829,
do stipulate as follows:

1. That while the invention has attained great perfection by the col-
laboration of M. Daguerre, the copartners recognize that the invention
has reached the point which it was intended to attain and that further
improvement seems to be almost impossible.

2. That since M. Daguerre, after numerous experiments, has realized
the possibility of accomplishing a more advantageous result regarding
the speed of operation by the aid of a new process discovered by him,
which (with the anticipation of certain success) would supplant the basis
of the discovery set forth in the provisory agreement of December 14,
1829, which discovery is explained there in detail, now therefore Article 1
of the mentioned provisory agreement is hereby canceled and the follow-
ing is substituted in its place.

Art. 1. A company is to be organized between MM. Daguerre and Isidore
Niepce, under the name “Daguerre and Isidore Niepce,” for the exploita-
tion of the invention made by M. Daguerre and the late Nicephore Niepce.

All the other articles of the provisory agreement remain unchanged by
the preceding.

Executed in duplicate for the undersigned at Paris, May 9, 1835.

Approved and acknowledged by our signatures

[(Signed] I. Niepce. Daguerre.

As Isidore Niepce reports in his Historique de la decouverte im-
proprement nommee daguerreotype (Paris, 1841) 2 that Daguerre had
shown him in 1837 proofs of light images which he had produced by
the use of iodine and mercury, it is, thus, in that year that photography
on iodized silvered plates with the development of the latent light
image by mercury vapors was invented. For the invention of the
development process Daguerre is said to have been indebted to a curious
accident. Daguerre exposed his silvered plates to the action of iodine
vapors, and in this way coated them with an extremely fine film of
iodide of silver; but on these plates no picture was produced in the

228 DEVELOPMENT WITH MERCURY VAPORS

camera obscura. His experiments, carried on for months and varied in
manifold ways, gave no result. Chance, however, in the most proper
sense, assisted him. A number of plates he had previously experimented
upon in the camera obscura had been put aside in an old cupboard and
had remained there for weeks without being further noticed. But one
day, on removing one of the plates, Daguerre to his intense astonish-
ment found on it an image of the most complete distinctness, the
smallest details being depicted with perfect fidelity. He had no idea
how the picture had come, but he felt sure there must be something
in the cupboard which had produced it. The cupboard contained all
sorts of things: tools and apparatus, chemical reagents, and among the
other things a basin filled with metallic mercury. Daguerre now re-
moved one thing after the other from the cupboard, with the exception
of the mercury, and still he regularly obtained pictures if the plates
which had previously been submitted to the action of images in the
camera obscura were allowed to remain for several hours in the cup-
board. For a long time the mercury escaped his notice, and it almost
appeared to him as if the old cupboard were bewitched. But at last it
occurred to him that it must be the mercury to whose action the pictures
were due. A drawing made with a pointed piece of wood on a clean
pane of glass, remains invisible even to the most acute sight, but comes
to light at once when breathed upon. The condensation of the watery
vapor (deposited in small drops) differs in the parts touched with the
wooden point and those left untouched, in the same manner as took
place in Daguerre’s pictures (Liebig, Cornhill Magazine, XII, 303;
Vogel’s Lehrbuch der Photograpbie, 1878, p. 4).

A definite agreement was concluded on June 13, 1837, between
Isidore Niepce and Daguerre, giving Daguerre the right to call the
new process by the name “Daguerre” alone. This final contract reads:

I, the undersigned, declare by this present writing that M. Louis Jacques
Mande Daguerre, painter, member of the Legion of Honor, has com-
municated to me a process of which he is the inventor. This process has
for its object the fixation of images obtained in the camera obscura, not
with colors, but with perfect gradations of tone from white to black.

This new process has the advantage of reproducing objects from sixty
to eighty times more rapidly than that which my father, M. Joseph Nice-
phore Niepce, invented, and M. Daguerre had perfected. For the exploita-
tion of that process a provisional agreement which is before us had been
drawn December 14, 1829, in which it is stipulated that the process men-

DEVELOPMENT WITH MERCURY VAPORS 229

tioned above is to be made public in the following manner: “process
invented by M. Joseph Nicephore Niepce and improved by M. L. J. M.
Daguerre.”

After this communication had been imparted to me, M. Daguerre con-
sented to transfer the new process— of which he is inventor and which
he has perfected— to the partnership founded according to the above-
mentioned provisory agreement, under the condition, however, that this
new process shall carry the name of Daguerre alone; but it can only be
made public simultaneously with the first process, in short, the name of
M. Joseph Nicephore Niepce figures always, as is right, in this invention.

By this present agreement it is and remains established that all the articles
and underlying principles of the provisory contract of December 14, 1829,
remain in force.

After this new agreement between MM. Daguerre and Isidore Niepce,
which forms the final contract which is spoken of in Article 9 of the pro-
visory contract, the said parties having decided to make public their various
processes, the manner of publication by subscriptions has been given.

The announcement of the publication of the processes appears in the
daily papers. The subscription list will be opened on March 15, 1838, and
closed on April 15 of the following year. The price of subscription will be
1,000 francs. The list will be in the hands of a notary, to whom the payment
is to be made by the subscribers, whose number is limited to four hundred.

The terms of subscription will be as favorable as possible. The processes,
however, cannot be made public until at least one hundred individual
subscriptions are received; if this number is not completed, the partners
will consider another method of publication.

If before the subscription opens an offer is received for the sale of the
process, the price accepted must not be less than 200,000 francs.

Executed in duplicate, accepted and signed at Paris, June 13, 1837, at
the residence of M. Daguerre in the diorama.

^Signed] Isidore Niepce. Daguerre.

Chapter XXV. daguerre and Isidore

NIEPCE ATTEMPT UNSUCCESSFULLY IN 1837 TO
SELL DAGUERREOTYPY BY SUBSCRIPTION; THEY
OFFER THEIR INVENTION TO THE GOVERNMENT;
ARAGO’S REPORT TO THE ACADEMY ON JANUARY
7, 1839; AGREEMENT ARRIVED AT JUNE 14, 1839

After the final papers had been signed on June 13, 1837, the two part-
ners made an appeal to art lovers and capitalists for the purpose of
disposing of the four hundred shares; but their appeals met with no
response, and the subscription which was opened on March 15, 1838,
did not meet with success.

When the attempt to exploit the process of daguerreotype was un-
successful, Daguerre and Niepce decided to offer their method to the
government. Daguerre approached Frangois Jean Arago, to whom
he imparted, under the seal of secrecy his processes and those of
Nicephore Niepce. It was fortunate that Arago possessed such a great
insight into the invention, which he received enthusiastically. He re-
ported the invention of the daguerreotype to the Academy of Sciences
on January 7, 1839. The secrecy, however, was not observed very
carefully, for the Gazette de France published a notice about it on
January 6, 1839, although without printing any details. 1 Through the
intervention of Arago and other influential persons Daguerre and
Isidore Niepce were able to meet the Minister of the Interior, Duchatel,
with the result that a preliminary agreement was drawn on June 14,
1839, which read:

Louis Philippe, King of the French, to those present and to come, greetings!

We have commanded and do command that the draft of a bill, the con-
tents of which follow, be submitted in our name to the Chamber of Deputies
by our minister, Secretary of State for the Department of the Interior,
whom we order to explain the underlying motives and to support the
negotiations.

First Article

The provisional agreement made on June 14, 1839, between the Minister
of the Interior, acting for the State, and MM. Daguerre and Niepce, Jun-
ior, is made a part of the present law and approved.

DAGUERRE AND ISIDORE NIEPCE
Second Article

231

To M. Daguerre is granted an annual pension for life of 6,000 francs;
to M. Niepce, Junior, is granted an annual pension for life of 4,000 francs.

Third Article

On the passage of this present law these pensions shall be recorded in the
book for civil pensions of the public treasury. They are to be paid in half
to the widows of MM. Daguerre and Niepce.

Given at the Palais de Tuilleries, June 15, 1839.

[(Signed] Louis Philippe.

For the King:

The Secretary of the Department of State

[(Signed] Duchatel.

The following agreement was entered between M. Duchatel, sec-
retary of the State Department on one side and MM. Daguerre (Louis
Jacques Mande) and Niepce, Junior (Joseph Isidore) , as parties of the
second part:

Art. 1. MM. Daguerre and Niepce pledge themselves to place in the
hands of the Ministry of the Interior a sealed package containing the his-
tory and most detailed and exact description of the invention mentioned.

Art. 2. M. Arago, member of the Chamber of Deputies and of the
Academy of Sciences, who is already acquainted with the methods of pro-
cedure mentioned, will meanwhile examine all parts of the said deposition
and prove their correctness.

Art. 5. The deposition is not to be opened and the description of the
process is not to be given publicly until the draft of the law here discussed
is accepted. After the acceptance of the bill M. Daguerre must, on demand,
in the presence of a commission appointed by the Minister of the Interior,
operate the process.

Art. 4. M. Daguerre, in addition, pledges himself to give in the same
manner the details of his process of painting and the physical apparatus
which characterizes his invention of the Diorama.

Art. j. He is obliged to make public all improvements of his inventions
whatsoever, which he may accomplish in the future.

Art. 6. As remuneration for the present agreement the Minister of the
Interior pledges himself to request from the Chambers for M. Daguerre,
who herewith signifies his acceptance, an annual pension for life of 6,000
francs.

For M. Niepce, who also joins in the acceptance, an annual pension for
life of 4,000 francs.

232 DAGUERREOTYPY DONATED TO THE WORLD

These pensions will be recorded in the register of Civil Pensions of the
Public Treasury. Half of these pensions will revert to the widows of MM.
Daguerre and Niepce.

Art. 7. In the case that the Chambers in their full sessions do not pass the
proposed bill for these pensions, the mutual agreement with all rights
will be declared null and void and the sealed package will be returned to
MM. Daguerre and Niepce.

Art. 8. This present agreement is to be registered with a stipulated fee
of one franc.

Executed in triplicate, Paris, June 14, 1839.

Attested signatures:

[[Signed] Duchatel
[[Signed] Daguerre
[[Signed] I. Niepce

For the attest of the copy corresponding with the original and attached
to the draft of the bill.

The Secretary of the Ministry of State

[[Signed] Duchatel

Chapter XXVI. bill for the purchase of

THE INVENTION OF DAGUERREOTYPY BY THE
FRENCH GOVERNMENT, WHICH DONATES IT TO
THE WORLD AT LARGE

After the preliminaries arranged at the meeting between the Min-
ister of the Interior, Duchatel, and MM. Arago and Daguerre and the
preparation of the mentioned bill by Duchatel, the King appointed a
joint commision, composed of members of the Chamber of Peers,
headed by Gay-Lussac, and members of the Chamber of Deputies,
headed by Arago, to examine and report on the bill to their respective
Chambers. 1 These reports follow:

Report

of the Commission of the Chamber of Deputies charged with the examin-
nation of a proposed bill granting, first, to M. Daguerre an annual and
life pension of 6,000 francs and, second, to the son of M. Niepce, an annual
life pension of 4,000 francs for the assignment to the State of their process
for the fixation of images obtained in the camera obscura.

DAGUERREOTYPY DONATED TO THE WORLD 233

Presented by M. Arago, Deputy of the East-Pyrenees, in the French
Chamber of Deputies, on July 3, 1839.

Gentlemen:

The interest aroused in this invention recently made public by M. Da-
guerre in this circle and elsewhere has been keen, enthusiastic, and unani-
mous. In all probability the Chamber awaits from its Commission no more
than the approval of the proposed bill which the Minister of the Interior
has presented. After careful consideration, however, the mandate with
which you have charged us seems to impose upon us other duties.

We believe, however, that, while heartily approving the happy idea to
grant a national reward to inventors whose interests cannot be adequately
protected by the ordinary patent laws, we must furnish proof in the begin-
ning of the cautious and scrupulous care with which this Chamber proceeds.

To subject a work of genius, such as that upon which we have to pass
today, to a critical examination will serve to discourage ambitious medi-
ocrity which might aspire to bring before this assembly its common and
ephemeral productions. This will prove that you place upon a high plane
the rewards which may be asked of you in the name of the national glory
and that you cannot consent to lower your standards or dim their luster
by a too lavish disposal of them.

These few words will serve to explain to the Chamber the lines we
followed in our examination.

1. Is the process of M. Daguerre unquestionably an original invention?

2. Is this invention one which will render a valuable service to archae-
ology and the fine arts?

3. Can this invention become practically useful? And, finally,

4. Is it to be expected that the sciences may derive any advantage
from it?

Arago proceeded to sketch earlier attempts with the camera, citing
historical notes on the work of Wedgwood and others, which, how-
ever, were not at all exhaustive, and briefly outlined the early labors
of Niepce and Daguerre. Arago continues:

The partnership agreement registered between Niepce and Daguerre
for the joint exploitation of their photographic methods was dated Decem-
ber 14, 1829. The later agreements between M. Isidore Niepce, the son,
as heir, and M. Daguerre mention first improvements which the Parisian
painter added to the method invented by the physicist of Chalon and,
secondly, entirely new processes discovered by M. Daguerre, capable of
(in the language of the original document) “reproducing images sixty to
eighty times more rapidly than the earlier process.” This will explain the
several articles of the contract between the Minister of the Interior on the

234 DAGUERREOTYPY DONATED TO THE WORLD

one hand and MM. Daguerre and Niepce, Junior, on the other, attached
to the proposed bill. It will be noted that we have just spoken when discus-
sing the labors of M. Niepce the qualifying words: “for the photographic-
printing from copper engravings.” As a matter of fact Niepce, after nu-
merous fruitless experiments, had almost given up the hope of being able
to fix images obtained directly in the camera obscura. The chemical
preparations which he used did not darken rapidly enough under the action
of light, for he required ten to twelve hours to produce the image and
during the long time of exposure the shadows of the objects represented
changed from one side to the other, so that the resulting pictures were
flat and monotonous in tones, lacking all the pleasing effects which arise
from the contrast of light and shade; and, furthermore, even apart from
these difficulties, one was never certain of a successful result, because after
taking innumerable precautions, inexplicable and accidental occurrences
intervened, and there was sometimes a passable result, or an incomplete
image resulted which showed here and there empty spaces, and, finally,
when exposed to sunlight, the sensitive coating, if it did not refuse to darken,
would become brittle and scale off.

When all these imperfections are enumerated and the nature and manner
of their elimination is explained, an almost complete account is obtained
of the credit which M. Daguerre deserves for the discovery of his method,
achieved after endless laborious, delicate, and costly experiments.

Even the feeblest light rays change the sensitive substance of the daguer-
reotype plate. This change is effected before the shadows thrown by the
sun have time to move appreciably. The results are assured if one follows
certain simple rules. Finally, the effect of sunlight on the finished pictures
does not diminish, even after years, either their purity, their brilliancy, or
their harmony.

Your commission has made the necessary arrangements, so that on the
day when the proposed bill is discussed all those Deputies who desire to
examine the examples of the daguerreotype process may form their own
opinions of the usefulness of this discovery. While these pictures are ex-
hibited to you, everyone will imagine the extraordinary advantages which
could have been derived from so exact and rapid a means of reproduction
during the expedition to Egypt; everybody will realize that had we had
photography in 1798 we would possess today faithful pictorial records of
that which the learned world is forever deprived of by the greed of the
Arabs and the vandalism of certain travelers.

To copy the millions of hieroglyphics which cover even the exterior
of the great monuments of Thebes, Memphis, Karnak, and others would
require decades of time and legions of draughtsmen. By daguerreotype
one person would suffice to accomplish this immense work successfully.

DAGUERREOTYPY DONATED TO THE WORLD 235

Equip the Egyptian Institute with two or three of Daguerre’s apparatus,
and before long on several of the large tablets of the celebrated work,
which had its inception in the expedition to Egypt, innumerable hierogly-
phics as they are in reality will replace those which now are invented or
designed by approximation. These designs will excel the works of the most
accomplished painters, in fidelity of detail and true reproduction of the
local atmosphere. Since the invention follows the laws of geometry, it
will be possible to re-establish with the aid of a small number of given
factors the exact size of the highest points of the most inaccessible structures.

These reflections, which the zealous and famous scholars and artists
attached to the army of the Orient cannot lightly dismiss without self-
deception, must without doubt turn their thoughts to the work which is
now being carried on in our country under the control of the Commission
for Historic Monuments. A glance suffices to recognize the extraordinary
role which the photographic process must play in this great national enter-
prise; it is evident at the same time that this new process offers economic
advantages which, incidentally, seldom go hand in hand in the arts with
the perfecting of production.

If, finally, the question arises whether art in itself may expect further
progress from the study of these images drawn by nature’s most subtle
pencil, the light ray, M. Paul Delaroche will answer us.

In a report, made at our request this celebrated painter states that Da-
guerre’s processes “are so far-reaching in the realization of certain essential
requirements of art that they will be the subject of observation and study,
even by the most able painters.” What he stresses most about photographic
images is their “unimaginable precision” of detail, which does not disturb
the repose of the masses and does not detract in any way from the general
effect. “The accuracy of the lines,” Delaroche continues, “the nicety of
form, are as perfect in Daguerre’s pictures as could be desired, and at the
same time one recognizes a broad and vigorous modeling as rich in tone
as it is in effect. . . . The painter finds in this process an easy way of
making collections for after-study and use which otherwise are obtainable
only at great expense of time and labor, and yet less perfect in quality,
no matter how great his talent may be.” After having opposed with excel-
lent arguments the opinions of those who imagined that photography
would be detrimental to our artists and especially to our skilled engravers,
M. Delaroche concludes his report with the remark: “In short the re-
markable invention of M. Daguerre is a great service rendered to the Arts.”

We will not presume to add anything to such testimony.

It will be recalled that among the questions which occupied us at the
beginning of this report was whether this invention can become of prac-
tical use? Without disclosing anything that must remain secret until the

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passage and promulgation of the bill, we can say that the plates on which
light produces the admirable picture images of M. Daguerre are plated
tablets, i. e., copper plates which have been coated with a thin deposit of
silver. Doubtless, it would have been more advantageous not only for the
comfort of travelers as well as from an economic point of view, if paper
could be used. Paper impregnated with silver chloride or silver nitrate was
indeed the first substance chosen by M. Daguerre, but the lack of sensitivity,
the confused image, the uncertainty as to results, and the accidents which
often happened during the operation of reversing lights and shadows
could not but discourage so skilled an artist. Had he pursued this direction,
his pictures would probably be shown in collections as experimental results
among the curiosities of physics, but assuredly would never have become
a subject for the consideration of this chamber. Finally, if it be said that
three or four francs, the cost of a plate such as M. Daguerre uses, seems
too costly, it is but fair to state that the same plate may serve successively
for the taking of a hundred different pictures.

The extraordinary success of M. Daguerre’s present process can be at-
tributed in part to the fact that he uses an extremely thin coating, a veritable
film. We need not concern ourselves here with the cost of the material
employed; in fact the price is too small for evaluation. Only one member
of the commission has seen the artist at work and has himseif operated the
process. It is, therefore, due to the personal responsibility of this Deputy
that we can present to the members of the Chamber daguerreotype from
the standpoint of practicability. Daguerreotype calls for no manipulation
which anyone cannot perform. It presumes no knowledge of the art of
drawing and demands no special dexterity. When, step by step, a few simple
prescribed rules are followed, there is no one who cannot succeed as
certainly and as well as can M. Daguerre himself.

The rapidity of the method has probably astonished the public more
than anything else. In fact, scarcely ten or twelve minutes are required
for photographing a monument, a section of a town, or a scene, even in
dull, winter weather.

In summer sunlight the time of exposure can be reduced to half. In the
southern climate two to three minutes will certainly be sufficient. We
must note, however, that the ten to twelve minutes exposure in winter, the
five to six minutes in summer, and the two to three minutes in the South
express only the actual time during which the sensitive plate receives the
image projected by the lens. To this must be added the time occupied by
the unpacking and mounting of the camera obscura, preparing the plate,
and the short time necessary for protecting the plate from the action of
light after the exposure. For all these manipulations perhaps a half to three
quarters of an hour may be required. Those who fondly imagine when

DAGUERREOTYPY DONATED TO THE WORLD 237

about to start on a journey that they will employ every moment when the
coach is climbing slowly uphill in taking the scenes, will be therefore
disappointed in their expectations. No less will be the disappointment of
those who, astonished by the success obtained by the copying of pages and
illustrations of the most ancient works, would dream of the photographic
images for the reproduction and multiplication of the daguerreotype by
means of lithographic print. Not alone in the moral world has every quality
its defects; this principle applies also to the Arts. The perfection, delicacy,
and harmony of the picture images are the result of the perfect smoothness
and incalculable thinness of the coating on which M. Daguerre operates.
If such a picture is rubbed or even lightly touched, or subjected to the
pressure of a roller, it is destroyed past redemption; but, who could
imagine anyone pulling apart a fine piece of lace or brushing the wings of
a butterfly? The member of the Academy who has known for several
months the preparations on which the beautiful designs submitted for our
examination are produced deems it inadvisable to utilize his knowledge of
the secret which had been entrusted to him by M. Daguerre, who had
honored him with his confidence. He felt that before entering upon further
research, thrown open to physicists by the photographic process, it
would be more delicate to wait until a national award had placed in the
hands of all observers the same means for further study. If we therefore
discuss the scientific advantages of the invention by our compatriot, we
can only hazard a conjecture. The facts, however, are clear and obvious,
and we need not fear that the future will discredit our statements. The
preparation used by M. Daguerre is a reagent, much more sensitive to the
action of light than any heretofore known. Never have the rays of the
moon, we do not mean in its natural condition, but focused by the greatest
lens or the largest reflector, produced any perceptible physical effect. The
plates prepared by M. Daguerre, however, bleach to such an extent, by the
action of the same rays, followed by a subsequent treatment, that we may
hope to be able to make photographic maps of our satellite. In other words,
it will be possible to accomplish within a few minutes one of the most pro-
tracted, difficult, and delicate tasks in astronomy.

An important branch of the science of observation and calculation, that
which deals with the intensity of light, photometry, has so far made little
progress. The physicist has no difficulty in determining the comparative
intensities of two lights, one next to the other and both simultaneously
visible; but there are only imperfect means for making such a comparison
when the condition of simultaneity is lacking, as when a light which is now
visible is to be compared with another light, which will not be visible until
after the first light has disappeared.

The artificial lights available to the observer for the purpose of com-

2 38 DAGUERREOTYPY DONATED TO THE WORLD

parison in the above-mentioned case are rarely permanent or of desirable
stability; and seldom, especially when we deal with stars, do our artificial
lights possess the sufficient whiteness. This is the reason for the great
discrepancies between the determinations of the comparative light in-
tensities of the sun and moon and the sun and stars, as given by equally able
scientists; for the same reason the most important conclusions are sur-
rounded by certain reservations, when they refer to the last-mentioned
comparisons concerning the humble position which our sun occupies
among the milliards of suns with which the firmament is bespangled; this,
even in the works of the least timid authors.

We do not hesitate to say that the reagents discovered by M. Daguerre
will accelerate the progress of one of the sciences, which most honors the
human spirit. With its aid the physicist will be able henceforth to proceed
to the determination of absolute intensities; he will compare the various
lights by their relative effects. If needs be, this same photographic plate
will give him the impressions of the dazzling rays of the sun, of the rays
of the moon which are three hundred thousand times weaker, or of the
rays of the stars. He can compare these impressions, either by dimming
the strongest lights with the aid of the excellent media which only lately
have been discovered, a description of which would be out of place here,
or by allowing the most intense rays to act only for a second, while con-
tinuing the action of the other rays to half an hour, as may be necessary.

Moreover, when the observer applies a new instrument in the study of
nature, his expectations are relatively small in comparison to the succession
of discoveries resulting from its use. In a case of this sort it is surely the
unexpected upon which one especially must count.

Does this sound like a paradox? A few citations will prove its accuracy.

Some children accidentally placed two lenses each in opposite ends of a
tube. They thus produced an instrument which enlarged distant objects
and represented them as if approached. Astronomers accepted this instru-
ment with the hope of being better able to observe stars, which had been
known for ages, but which up to that time could be studied only im-
perfectly. Pointing this new instrument toward the firmament, they re-
vealed myriads of new worlds. Penetrating the inner formation of the six
planets of the ancients, one finds them similar to our own world, with
mountains the height of which can be measured, atmospheric disturbances
which can be followed, with the phenomena of formation and fusion of
polar ice, analogous to the terrestial poles and to the rotating movement
which corresponds to that which creates the succession of our days and
nights. Pointed toward Saturn, the tube of the Middelburg spectacle
maker’s children reveals a phenomenon more wonderful than any dream
of the most fanciful imagination.

DAGUERREOTYPY DONATED TO THE WORLD 239

Could anyone have foreseen that when turned so as to observe the four
moons of Jupiter it would reveal luminous rays, traveling at a speed of
eighty thousand miles (300,000 km.) per second; that, attached to graduated
measuring instruments it would demonstrate that no stars exist whose light
reaches us in less than three years; and, finally, that if the instrument be
used in certain observations one may conclude with reasonable certainty
that the rays by which we perceive at any given moment were emitted by
certain nebulae millions of years ago; in other words, that these nebulae,
owing to the continuous propagation of light, would be visible to us several
millions of years after their complete destruction?

The glass for near objects, the microscope, gives occasion for similar
observations, because nature is no less admirable, no less varied in its small-
ness than in its immensity. When the microscope was first used for the
observation of certain insects whose shapes the scientists desired to see
in an enlarged size in order to delineate them more accurately, it revealed
subsequently and unexpectedly in air, in water, in short in all liquids,
these animalcules, these infusoria, through which it is hoped to find sooner
or later a reasonable explanation for the beginning of life. Recently directed
to minute fragments of different stones of the hardest and most solid
variety, of which the crust of our earth is composed, the microscope re-
vealed to the astonished gaze of the observer that these stones once lived,
that they are in reality a conglomeration of milliards and milliards of
microscopic animalcules closely cemented together.

It should be remembered that this digression was necessary in order to
dispell the erroneous opinion of those who would mistakenly limit the
scientific application of M. Daguerre’s processes to the outline we have
given; indeed, the facts already justify our expectations. We could, for
instance, cite certain ideas, for the rapid method of investigation, which
the topographer could borrow from the photographic process, but we shall
reach our goal more quickly by mentioning here a singular observation,
of which M. Daguerre spoke to us yesterday. According to him, the hours
of the morning and of the evening, which are equally distant from the noon
hour, and at which times the sun is at the same altitude, are not, however,
equally favorable for the taking of photographs.

Thus, a picture is produced, regardless of the season and under similar
atmospheric conditions at seven o’clock in the morning somewhat more
rapidly than at five o’clock in the afternoon; at eight o’clock faster than at
four o’clock, at nine faster than at three. Supposing this result is to be
verified, the meteorologist will have a new element to record in his tables,
and to the ancient observations as to the state of the thermometer, barometer,
and hygrometer and the visibility of the air they will have to add another
element, which these early instruments do not indicate. It will be necessary

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to take into consideration an absorption of a peculiar character which can-
not be without influence on many other phenomena, perhaps even on those
belonging to the fields of physiology and medicine.

We will endeavor, gentlemen, to set forth everything which the dis-
covery of M. Daguerre offers of interest under four aspects: its originality,
its usefulness in the arts, the speed of execution, and the valuable aid which
science will find in it. We have striven to make you share our convictions,
which are vivid and sincere, because we have examined and studied every-
thing with scrupulous care, in keeping with the duty imposed by your
suffrage, because, if it were possible to misjudge the importance of the
daguerreotype and the place which it will occupy in the world’s estimation,
every doubt would have vanished at sight of the eagerness with which
foreign nations pointed to an erroneous date, to a doubtful fact, and sought
the most flimsy pretext in order to raise questions of priority and to try to
take credit for the brilliant ornament which photography will always be
in the crown of discoveries. Let us not forget to proclaim that all discussion
on this point has ceased, not so much on account of the incontestable and
authenticated authority of title on which MM. Niepce and Daguerre base
their claims, but chiefly because of the incredible perfection which M.
Daguerre attained. If it were necessary, we would not be at a loss to present
here the testimony of the most eminent men of England and Germany, in
the face of which everything we have said, however flattering, concerning
the discovery of our compatriot would pale completely. France has
adopted this discovery and from the first moment has been proud that it
can present it generously to the entire world.

We were not at all surprised by the public sentiment awakened by the
exposure, due to a misapprehension of motives, which seemed to indicate
that the government had bartered with the inventors and that the pecuniary
conditions of the contract proposed for your sanction represented a bargain.
It becomes necessary, gentlemen, to re-establish the facts.

The member of the Chamber who had full power given him by the
Minister of the Interior did not haggle with M. Daguerre. Their negotiations
were concerned solely with the point whether the recompense which the
able artist had so well merited should be a fixed pension or a single payment.
M. Daguerre at once remarked that the stipulation of a lump sum might
give the contract the character of a sale. It would not be the same with a
pension. It is with a pension that you reward the soldier, crippled on the
field of honor, the official, grown gray at his post; and thus you have
honored the families of Cuvier, Jussieu, De Champollion.

Such memories must have affected the noble character of M. Daguerre;
he decided to ask for a pension. At the request of the Minister of the
Interior, M. Daguerre himself set the amount of the pension at 8,000 francs,

DAGUERREOTYPY DONATED TO THE WORLD 241

which was to be divided equally between him and his partner, M. Niepce’s
son. M. Daguerre’s share was later increased to 6,000 francs, partly because
of the special conditions imposed on this artist, namely, to reveal the
process of painting and lighting of the canvasses of the diorama, now re-
duced to ashes, and especially because he has pledged himself to make pub-
lic all improvements with which he may enrich his photographic methods.
The importance of this pledge will certainly not seem doubtful to anyone
when we state that only a little progress is required to enable M. Daguerre
to make portraits of living persons by his process. As far as we are con-
cerned, instead of fearing that M. Daguerre might delegate to others the
labor of adding to his present success, we rather sought to moderate his
ardor. This we frankly admit is the motive which induced us to desire that
you declare the pension free from the laws of restraint and attachment,
but we have found that this amendment will be superfluous according to
the law of 22d Floreal of the VII year and according to the decree of the
7th Thermidor of the X year.

The commission therefore unanimously proposes that you adopt the
bill of the government without change.

In the House of Peers the celebrated chemist Joseph Louis Gay-
Lussac reported in equally warm words, as follows, at the session of
July 30, 1839.

Report

made to the Chamber of Peers by M. Gay-Lussac in the name of the
special commission 2 charged with the examination of the bill relating to
the acquisition of a process invented by M. Daguerre to fix the images of
the camera obscura.

Gentlemen:

Everything which contributes to the progress of civilization, to the
physical or moral well-being of man, must be the constant object of solici-
tude to an enlightened government, always alert to the duties with which
it has been entrusted; those who, by their fortunate effort aid this noble
task must find their honorable recompense in their success. Hence protec-
tive laws apply to literary and industrial property and assure to the author
benefits proportional to the importance of the services rendered to society;
a mode of remuneration which is so much more just and more honorable,
because it is a purely voluntary contribution in return for services rendered
and a shelter from the caprice of favoritism. While, however, this mode
of encouragement is best suited to most circumstances, there are some
where it cannot be applied or is impracticable or inadequate, and others
where great discoveries demand more conspicuous and distinguished re-
wards.

242 DAGUERREOTYPY DONATED TO THE WORLD

It seems to us, gentlemen, that the discovery of M. Daguerre belongs to
this category, and thus it has been regarded by the Royal Government,
which has made it the subject of the present bill laid before you for your
approval, and by the Chamber of Deputies, which has already given legis-
lative sanction to the bill.

M. Daguerre’s discovery is known to you by the results which have been
presented to you and by the report to the Chamber of Deputies of the
illustrious scientist to whom the secret was confided. It is the art of fixing
the image obtained in the camera obscura on a metallic surface and con-
serving it.

Let us hasten, however, to remark, without intending in any way to
belittle the merits of this beautiful discovery, that the palette of this painter
is not very rich in colors; black and white alone comprise it. The image
with its natural and varied colors will for a long time, perhaps for ever,
remain a challenge to human ingenuity. We shall not venture, however,
to confront him with unsurmountable barriers; M. Daguerre’s success opens
the way to a new order of possibilities. Called upon to give our opinion
on the importance and future of M. Daguerre’s invention, we have based
it on the very perfection of the results, on the report of M. Arago to the
Chamber of Deputies, and upon new communications received from this
scientist and from M. Daguerre. Our conviction as to the importance of the
new process is confirmed, and we should be happy, indeed, to have the
Chamber share it with us.

It is certain that through M. Daguerre’s invention physics is today in
possession of a reagent extraordinarily sensitive to the influence of light,
a new instrument which will be to the study of the intensity of light and
of luminous phenomena what the microscope is in the study of minute ob-
jects, and it will furnish the nucleus around which new researches and new
discoveries will be made. Already this reagent has recorded a very distinct
impression of the dim light of the moon, and M. Arago has expressed the
hope for a map of this satellite traced by the moon herself.

The Chamber had the opportunity to convince itself from the exhibits
that bas-reliefs, statues, and monuments, in one word, inanimate nature,
are reproduced with a perfection unattainable by the ordinary methods
of drawing and painting, equal to nature itself, because in fact M. Daguerre’s
pictures are nothing other than the veritable images.

The perspective of the landscape and of each object is delineated with
mathematical exactness; each incident, each detail, even if imperceptible,
cannot escape the eye and the brush of this new painter, and since three
or four minutes suffice for the work, a battle scene may be recorded in
its successive phases with a perfection unattainable by any other means.

The industrial arts will certainly make general use of M. Daguerre’s

DAGUERREOTYPY DONATED TO THE WORLD 243

process for the representation of forms, for designing perfect examples of
perspective, and for the study of light and shade; the natural sciences, f or the
study of the species and their organization. Finally, the problem of its appli-
cation to portraiture is almost solved, the few difficulties yet to be overcome
leave no doubt as to success. However, we must not overlook the fact that
colored objects are not reproduced in their natural colors and that, since
the different luminous rays do not act uniformly on M. Daguerre’s reagent,
the harmony of the light and shade effects of the colored objects necessarily
is altered. Here is the point of arrest, nature herself imposing her limitations
on the new invention.

Such, gentlemen, are the advantages already assured, and the expecta-
tions of immediate fulfillment of M. Daguerre’s discovery. Meanwhile,
further information regarding the manipulation of the process was neces-
sary, and the commission thought that no one would be better qualified to
obtain it in a manner more certain and authentic than the honorable Deputy
himself, in whom M. Daguerre had placed his confidence, and later the
Minister of the Interior and the other Chamber. M. Arago, on the invita-
tion of the president of the commission, attended their session and con-
firmed with new additional details what he had stated in his interesting
report. It is established that the practicable working of M. Daguerre's pro-
cess will require only a very short time and a negligible expense after the
initial investment of approximately four hundred francs for the apparatus.
Everyone is sure of success after a few trials. M. Arago himself, after
having been initiated, produced a successful result which we would un-
doubtedly have been anxious to see; unfortunately, it was destroyed by
the flames which consumed the diorama.

If further testimony were needed, the reporter of your commission may
add that M. Daguerre offered to make him also acquainted with the secret
of his process and that he described to him the complete procedure. The
speaker can affirm that the process is inexpensive and that it can be operated
by persons entirely inexperienced in the art of drawing, if they follow the
instructions which M. Daguerre has undertaken to publish and to demon-
strate. In his own interest, as well as in that of his process, success is essential,
and there can be no d<?ubt that M. Daguerre is anxious to insure it.

Your reporter adds that although he did not make a practical test of the
process himself as did his respected friend M. Arago, he can judge from
the descriptions which were offered him that its discovery involved many
difficulties at a great expense of time and innumerable experiments in par-
ticular, that it called for a perseverance, not to be discouraged by failure,
such as is possessed only by great souls. The process is, in fact, composed
of successive operations which do not necessarily relate to each other, and
their effects are not recognized immediately after each single step, but only

244 DAGUERREOTYPY DONATED TO THE WORLD

in their combined result. Surely, if M. Daguerre desired to carry on his
process by himself or to confide only in wholly trustworthy persons, he
would not need to fear that he would be robbed of the fruits of his labors.
The questions may be asked and have already been put: Why, if the process
is so difficult to discover, did he not exploit it himself? And why, under
our wise laws, which secure the interests of the inventor as well as those
of the public, did the government decide to acquire the invention and
donate it to the public? We shall answer both questions.

The principal advantage of M. Daguerre’s process consists in obtaining
rapidly and accurately images of objects, either to preserve them as such
or to reproduce them by means of engraving or lithography; and this being
so, it will be easily understood that the process in the hands of a single
individual could not reach its full development.

On the other hand, made available to the public, the process will find
manifold applications in the hands of the painter, architect, traveler, and
scientist.

Finally, if held closely by an individual, the process would remain where
it is for a long time and perhaps fade from the scene. As public property,
it will develop and be improved by the co-operation of the many. Thus
from various aspects it is desirable that the process should become public
property. In these circumstances it became the duty of the government
to show its interest in Daguerre’s process and to provide adequate com-
pensation for its author. To those who are not indifferent to national
glory, and who know that a people excels in achievement over other peoples
only in proportion to their respective progress in civilization, to those we
can say that the process of M. Daguerre is a great discovery. It is the begin-
ning of a new art in an old civilization; it means a new era and secures for
us a title to glory. Shall we pass it on to posterity accompanied by the
ingratitude of its contemporaries? Should it not come rather as a brilliant
testimonial of the protection accorded to great inventions by the Chambers,
the July Government, and by the whole nation?

In reality, it is an act of national munificence expressed by the proposed
bill in favor of M. Daguerre. We have given it our unanimous approval,
but not without remarking the importance and honor attaching to a
national reward. We call attention to this to remind ourselves, not without
regret, that France has not always been so grateful and that only too often
have beautiful and useful works earned for their inventors nothing but
empty glory. This should not be interpreted as an accusation; errors should
be deplored in order to avoid their repetition.

Gentlemen, having appraised to the best of our ability, the importance
of M. Daguerre’s invention, we reaffirm our conviction that it is new, rich
in interest and possibilities, and, finally, well worthy of the high honor

DAGUERREOTYPY DONATED TO THE WORLD 245

of the national reward which has already been granted by the Chamber
of Deputies. The commission voted unanimously in favor of the pure and
simple adoption of the bill, and I, as its reporter, have been charged to
propose that you do likewise.

The bill was passed in the Chamber of Deputies on July 3, 1839, and
in the upper Chamber on July 30, with two hundred and thirty-seven
votes against three. Thereupon Arago reported an exact description
of the photographic processes of Niepce and Daguerre at the session
of the Paris Academy of Sciences on August 19, 1839, and this presen-
tation was received with enthusiasm by an enormous crowd.

On August 14, 1839, Daguerre’s invention was granted a patent in
England.

At the time of the publication of daguerreotypy, Hofrat von Ettings-
hausen, professor of physics at the University of Vienna, was present
in Paris, under orders from the Austrian government, and interested
himself keenly in Daguerre’s invention. Earlier the Austrian chancellor,
Prince Clemens Metternich, had received reports about Daguerre
through Count Apponyi, who was the royal and imperial Austrian
ambassador at Paris from 1826 to 1849. It seems that he invited Pro-
fessor Ettingshausen to report to him personally and that he promoted
his studies and interests. Ettingshausen was able to study Daguerre’s
method under him, reported to Prince Metternich at his Johannisberg
castle on the Rhine, and brought the daguerreotype process to Vienna.
When detailed descriptions of the process became known through
the scientific journals, the assistant in the faculty of physics at the
Polytechnikum and later the librarian, A. Martin, also Dr. J. J. Pohl,
who was then a student, the apothecary Endlicher, Regierungsrat
Schultner, as well as Wawra (father of the art dealer), busied them-
selves with the production of daguerreotypes. From this circle came
A. Martin’s Repertorium der Photo graphie (1846), the first book in
Germany which discussed unselfishly the experiences and experiments
of these workers and published detailed information on the publica-
tions of other scientists relating to the progress of daguerreotypy.

Chapter XXVII. daguerre’s activities

AFTER THE PUBLICATION OF DAGUERREOTYPY;
REPORT ON DAGUERREOTYPY TO THE EMPEROR
OF AUSTRIA

During this whole period Daguerre resided in Paris. Until 1839 he
lived at 15 Rue de Marais, the premises of the diorama from which
he derived his income. In 1839 the house was burned to the ground,
and with it the irreplaceable first results of Daguerre’s work. Among
these was the experimental picture which Daguerre made with Arago
in order to instruct the latter in the method and importance of his
invention. In the summer of 1839 Daguerre, who was married, lived
at 17 Boulevard St. Martin, where he liked to spend his time in the
circle of his friends; 1 but he did not neglect the further development
of his invention and accepted the honors conferred upon him with
joyful gratitude.

Daguerre had sent two daguerreotypes to Prince Mettemich even
before the detailed publication of his process. These incunabula of
daguerreotypy were preserved for many years in the physics collection
of the imperial residence of the Palace in Vienna, where Crown Prince
Rudolph received his practical instruction. After the death of the
Crown Prince the collections were divided among many schools and
were lost. The subjects of the daguerreotypes, however, are known
from the reports of contemporaries.

Emperor Ferdinand I of Austria was probably the first monarch,
except the French sovereign, who manifested a particular interest in
Daguerre’s invention after it became known. He treated him with
marked distinction on account of a report, dated August 24, 1839, by
the Chancellor Prince Metternich, whose keen insight grasped the
importance of photography for the future. Through the courtesy of
Freiherr Dr. von Weckbecker, Vienna, the author was privileged to
study other, hitherto unknown documents referring to Daguerre in
the imperial archives. The Emperor had received early in August one
of Daguerre’s first specimens, for which he ordered a valuable hono-
rarium to be transmitted in return to Daguerre.

The Emperor’s letter to the Lord Chamberlain, Count Czemin, dated
September 2, 1839, is signed by him. The text is as follows:

Dear Count Czemin.

Through my Embassy at Paris, M. Daguerre has sent a specimen picture
of his invention, fixing by the action of light the images obtained in the

DAGUERREOTYPY AND FERDINAND I

2 47

camera obscura, for which I grant him an artist’s medal, 18 ducats in
weight, and an initialed snuffbox valued at 1,200 florins. You are ordered
to expedite both to my House, Court and State Chancellor, Prince
Mettemich, that he may present them to M. Daguerre.

Schonbrunn, September 2, 1839.

^Signed] Ferdinand.

It is interesting to note the following sentence from the instructions
for the engraving of the medal:

Since according to the specifications the name of the party is to be en-
graved, and the office of the Chancellor has been unable to procure any
knowledge of his Christian name, the office of the Lord Chamberlain deems
it proper to employ the expedient used previously on similar occasions and
to entrust the commission to the Imperial Royal Embassy at Paris, request-
ing that Daguerre’s name be ordered engraved on the said medal, in order
that the early acknowledgment of this gracious act, which the Court and
State Office hereby requests, be not delayed.

This shows the high esteem in which Daguerre’s invention was held
at the Austrian Court and how his first daguerreotypes were appre-
ciated— in a manner in which only distinguished artists were honored.

The first daguerreotypes sent to Vienna were exhibited at the
Wiener Maler-Akademie, in 1839. The academy proposed to the
government, in 1840, that Daguerre be made an honorary member of
the Vienna Academy. This proposal, however, was not honored until

1 843 :

It is unfortunate that the pictures which Daguerre sent to the Em-
peror of Austria and to Prince Metternich have been lost, but an exact
description of them is preserved in the Vienna journals of that time.
For instance, Der dsterreichiscbe Zuschauer, September 20, 1839, No.
1 1 3, writes as follows:

Both pictures are framed, under glass. One of them, a view of Notre Dame,
Paris, presents the view of a whole section of the town. In the middle fore-
ground one sees the Gothic Church (Notre Dame). Alongside is a bridge
crossing the Seine, on each side the embankments, and in perspective rows
of houses. The scale is probably 1/1000 of the natural size. It is necessary
therefore to use a magnifying glass in order to view the details of the pic-
ture. And then the tiny pointed arches of the church windows, the smallest
architectural ornament, hardly perceptible to eye in reality, every brick,
the iron railing on the bridge, the stones of the pavement, in short, the
smallest trifle is shown in such perfection that any other image is poor in
comparison. It is the same with lights and shadows. The draughtsman

2 48 COMMERCIAL USES OF DAGUERREOTYPY

must lay down his pencil, the engraver his tool and confess that he cannot
now or ever equal this result. The second picture, representing the studio
of M. Daguerre, falls short of the first in point of sharpness and perfection,
presumably because the light in the closed room was not as strong as that
in the open air. We see in the foreground a plaster of Paris statue of Her-
cules, which shows very bright and therefore most distinctly. On the floor
next to it is a sphinx, and several plastic objects— casts of hands, feet, etc —
fill the intermediate space. In the background on the left stand the Three
Graces, carrying an entablature as Caryathides. In all the statues, par-
ticularly in that of Hercules, every muscle, every shadow, and every half-
tone is expressed in detail. The coloring is like that of a copperplate en-
graving, only translating gray into gray, but there are found here effects
which are indescribable, and everyone was obliged to confess that he had
never seen anything like it.

This demonstrates the overwhelming impression which the first da-
guerreotypes made in Austria.

Chapter XXVIII. success of daguerreo-

TYPY AND ITS COMMERCIAL USE; THE FIRST DA-
GUERREOTYPE CAMERAS, 1839

The success of Daguerre was extraordinary in every respect. In 1839
he became an Officer of the Legion of Honor, was elected an honorary
member of the Royal Society of London (August, 1839), of the
National Academy of Design, New York (May, 1839), and of the
Vienna Academy (1843). In the spring of 1843 King Frederick Wil-
liam IV of Prussia bestowed on Daguerre at the request of Humboldt
the order “Pour le Merite,” which was seldom given to foreigners. He
received many other honors; but regardless of these rewards he did not
neglect the financial side of his invention. He drew large profits from
the sale of daguerreotype cameras and auxiliary apparatus.

THE YEARS PRECEDING DAGUERRE’S DEATH 1

In the early forties of the last century Daguerre retired from business,
greatly respected and amply rewarded. He made his home at his
country place in Petit-Bry-sur-Marne, where he received visitors from
all countries; there he died, suddenly, July 10, 1851. Daguerre left
no will, but he had adopted his niece, Eulalia Daguerre, later Madame
Courtin, who inherited his objects of art and his estate.

COMMERCIAL USES OF DAGUERREOTYPY 249

PORTRAITS AND MONUMENTS

There are several portraits of Daguerre in existence, and we refer
only to those which seem most interesting. [These are reproduced in
the fourth edition, 1932, of this History. Potonniee, in his Histoire,
reproduces a miniature by Millet de Char lieu, painted in 1827 and
preserved in the Louvre.

A good portrait of Daguerre is shown in a lithograph by Aubert,
dating from the late twenties. It was exhibited at the Paris Exposition
in 1900. Especially valuable is the portrait ascribed by the editors of
The Year Book of Photography to Mayall of London (1846), but
according to George E. Brown ( The Photogram, 1903, p. 323; The
Photo-Miniature, March, 1904) it is a daguerreotype by Charles Meade,
of New York, who visited Daguerre at Bry in 1848; it certainly dates
from Daguerre’s last years 2 and presents him as a country gentleman
in robust health. Another good portrait appears in Nadar’s Paris-
Photographe (1891, No. 1, p. 23) a heliogravure reproduction of a
daguerreotype.

In a print in a Dutch textbook on photography by Idzerda, Leer bock
der algemeene Fotografie (1909, p. 101) Daguerre is pictured as a
photographer, seated at a table on which rests a camera, probably illus-
trating the earliest form of the Daguerre-Giroux camera of 1839-40.

A monument adorned with a medallion portrait of Daguerre was
erected in the cemetery at Petit-Bry-sur-Marne by the Societe Libre des
Beaux Arts, of which Daguerre was a member, on November 4, 1852,
a year after his death. A larger bust in bronze, by Elsa Bloch, was un-
veiled on the Place Carnot at Bry-sur-Marne on July 27, 1897, donated
by international subscriptions. 3

America also possesses its monument of Daguerre, erected at Wash-
ington in 1890 by the Photographers’ Association of America (An-
thony’s Photographic Bulletin, Feb. 8, 1890, XXI, frontispiece).

A number of commemorative medals, presented by various photo-
graphic societies for meritorious services in the field of photography,
display the portraits of Niepce and Daguerre. Especially worthy of
mention is the beautiful Peligot medal of the Societe frangaise de
Photographic, at Paris, executed by E. Soldi. This medal was instituted
by the celebrated chemist Eugene Melchior Peligot and is considered
one of the coveted prizes of the Paris Photographic Society. The Klub
der Amateur-Photographen, in Vienna, also had a Daguerre medal
stamped, by Jauner of Vienna.

2 5 0 COMMERCIALIZATION OF DAGUERREOTYPY

Many controversies have arisen as to whether Niepce or Daguerre de-
served the greater share of the merit for the invention of photography.
The author of this history is convinced that the credit unquestionably
belongs to Nicephore Niepce, for having been the first to produce
photographs in the camera and to have fixed images on asphaltum. He
is also without doubt the inventor of heliography, which made pos-
sible the photomechanical reproduction of pictures by the printing
press. Daguerre had attempted to produce light images since 1824, but
without success. It was not until he was made familiar with Niepce’s
new ideas and experiments and after he had changed, developed, and
modified them successfully that images were obtained in the camera
obscura with a relatively short time of exposure. After all, in both
Niepce’s and Daguerre’s methods silvered plates were used as a basis.
Both used iodine, but as shown above, in an entirely different manner.
The great achievements were the first use of silver iodide as a light-
sensitive substance in the camera obscura, the discovery of the develop-
ment of the scarcely visible image by mercury vapors, and the discovery
of the fixation of silver images. These rightly belong to Daguerre alone.
The similarity of the methods of the two inventors would lead us to
suppose that without Niepce’s ideas it would have been difficult for
Daguerre to have discovered the art named after him; but it is equally
probable that the valuable discovery of Niepce would have been in
vain without Daguerre’s collaboration. In the history of science they
must in justice be named jointly, and Niepce and Daguerre have equal
claims on public gratitude.

NOTE

An alleged predecessor of Daguerre, the Greek monk Panselenus,
whose writings a Dr. Simonides is supposed to have discovered, is dealt
with exhaustively in the British Journal of Photography (1865, XII,
7 3, 1 94) , by Carey Lea, who rejects this claim as quite unjustified.

Chapter XXIX. commercialization of da-

GUERREOTYPY; DESCRIPTION OF THE PROCESS

Daguerre was not only a successful inventor and artist but also a
clever business man. In 1839 he joined Giroux, manufacturer of cameras
in Paris, for the commercial introduction of his camera. This camera

COMMERCIALIZATION OF DAGUERREOTYPY 251

had affixed to it, as a guarantee, the signature of Daguerre and the seal
of Giroux. A label on the wooden box of the camera read: “Each
apparatus is guaranteed only if it carries the signature of M. Daguerre
and the seal of M. Giroux. Equipment for daguerreotypy furnished,
under the direction of its author, in Paris by Alph. Giroux et Cie., Rue
de Coq. St. Honore, No. 7.”

Illustration No. 58 in the German edition ( Geschichte der Photo-
graphic, 4th ed., 1932, p. 329) shows an orignial Daguerre camera, 1
as supplied by Giroux in September, 1 8 39, at a price of 400 francs. One
may recognize the movable telescopic wooden box and the dia-
phragmed lens which could be closed by a simple metal cover, an
achromatic lens manufactured by Charles Chevalier in Paris.

Chevalier’s lens consisted of a simple achromatic lens which com-
bined a biconvex and a biconcave flint glass. (See the reference to
Wollaston’s meniscus, used earlier by Niepce) . Thislens was achroma-
tized to optical rays as John Dollond had indicated and as Fraunhofer
had taught. It was very slow, but it sufficed for the early period of
daguerreotypy, being employed chiefly for exposures of architectural
subjects and landscapes. The achromatization for the optical and chem-
ical rays was perfected much later, when Petzval discovered his epoch-
making portrait lens, concerning which more can be found in my
Handbuch (1893 , 1 (2), 56).

John Dollond (1706-61) was born in London and became a silk
weaver by trade. He also studied mathematics, optics, and astronomy.
In 1768 he discovered the unequal dispersion of colored light rays in
various refracting media and deduced from this the possibility for the
construction of telescopes, which did not produce colored rings. In
1757 he constructed an achromatic telescope of flint and crown glass
( Kelly, Life of John Dollond, 3 d ed., 1 908 ) . Dollond’s lenses, however,
were corrected by empirical tests. Fraunhofer was the first one to teach
the exact calculation for the correction of color errors.

It is characteristic of Daguerre’s well-developed business acumen
that on August 14, 1839, a few days before the daguerreotype process
was made public at a meeting of the Paris Academy, Miles Berry ap-
plied for an English Patent (No. 8,194, 1 8 39) for daguerreotypy, “Be-
ing a communication from a foreigner residing abroad,” I quote from
the patent, “I believe it to be the invention or discovery of MM. Louis
Jacques Mande Daguerre and Joseph Isidore Niepce, Junior.” These
patent rights were bought by Claudet, who utilized them in his en-

2 5 2 COMMERCIALIZATION OF DAGUERREOTYPY

deavor to shorten the time of exposure. He introduced important im-
provements into daguerreotypy. Claudet succeeded by his clever ser-
vices in bringing the process into high public esteem and was appointed
court photographer to the Queen and the Prince-Consort Albert
(1855).

THE FIRST DESCRIPTION OF THE PRODUCTION OF DAGUERREOTYPES

The first report on the discovery of Daguerre was made by Arago on
January 7, 1839, to the Royal French Academy of Sciences. The com-
plete public report, entitled “La Daguerreotype, origine et histoire
de cette decouverte,” was delivered on August 19, 1839, and may be
found in Comptes rendus.

The first official description of the daguerreotype process made
accessible to the general public was published in the handbook His-
torique et description des procedes du daguerreotypie et du diorama ,
by Louis Jacques Mande Daguerre (pp. iv, 79, with six plates illus-
trating the apparatus used; Paris, Susse Freres, 1839) . A second edition,
corrected and enlarged, with a portrait of Daguerre as frontispiece,
was published by Giroux, and a third edition, with the imprint of F.
Mollet, Paris, appeared in the same year. An English edition, Historical
and Descriptive Account of the Various Processes of the Daguerreo-
type and of the Diorama, by an unnamed translator, was published in
1839 by McLean and Nutt, London, with portrait and six plates. The
first original German edition was published in 1839, by Schlesinger, in
Berlin. W. Knapp, in Halle, also published in 1839 a booklet by F. A.
W. Netto, entitled Vollstdndige Anweisung zur Verfertigung da-
guerrescher Bilder.

These were followed by a great output of literature, some of which
has become very rare. An exhaustive list is given in the treatise of Eder
and Kuchinka, Die Daguerreotypie und die Anfdnge der Negativ-
photographie auf Papier und Glas ( Talbotypie und Niepfotypie)
( Handbuch , 1927, Vol. II, Part 3). Most of these pamphlets and books
appeared in the early forties— until about 1 847.

A very complete and valuable collection of early publications deal-
ing with photography was gathered by the author of this history for
the library of the Graphische Lehr- und Versuchsanstalt, of Vienna.
The library of the Technical College at Vienna also, by the efforts of
the late librarian, A. Martin, possesses an important collection, and there
are notable collections in the libraries of the principal French, German,
English, and American photographic societies.

COMMERCIALIZATION OF DAGUERREOTYPY 253

DAGUERREOTYPY IN POPULAR USE, 1 8 39

The publication of the daguerreotype process aroused great interest
throughout the world. It was introduced into use before the end of
1839 in many countries outside of France; the demands for its acces-
sories therefore grew tremendously. A complete apparatus, including
camera with lens, silvered plates, chemicals, and so forth, cost 400 francs.
Original daguerreotypes made in Paris brought in Germany and else-
where at the end of 1839 from 60 to 120 francs. The first pupils of
Daguerre sold their own daguerreotypes at this time for about twenty
to twenty-five marks.

DESCRIPTION OF DAGUERRE’S PROCESS

The original camera of Daguerre consisted of a plain wooden box
with a simple Chevalier lens 2 of flint and crown glass cemented to-
gether. By means of a mirror fixed at an angle of 45 0 behind the ground
glass (focusing glass) of the camera, the spectator viewed the pic-
ture image from above, seeing the subject (reversed by the mirror) in
its original upright position, that is, “right side up,” as in the reflex
cameras of today. A light-sensitive silvered copper plate, 3 usually 6.5 x
8.6 inches, carefully polished and previously subjected to the vapors
of iodine at normal temperature, this forming a very thin coat of silver
iodide, was used to receive the picture image. In the camera these sil-
vered plates treated with iodine vapors, were exposed to light for such
a long time that at first one had to be satisfied with “taking” inanimate
objects, such as architectural subjects, those of the plastic art, and land-
scapes. The first daguerreotypes were reversed as to position, but soon
(1841) Chevalier attached to the front of the lens tube a reversing
prism with a silvered hypothenuse and offered this apparatus for sale.

For the development of the invisible camera image the iodized sil-
vered plates were subjected to the vapor of mercury, slightly heated.
This was done in a wooden mercury box with a saucer-like hollow iron
bottom in which the mercury was placed. An alcohol lamp on a shelf
below heated the mercury, and a thermometer on the inside of the box
indicated the correct temperature. After the exposure, the plate was in-
serted in the box diagonally, the cover closed and the image gradually
became visible (developed) through the action of the mercury vapor. 4

Daguerre himself and his numerous pupils produced many da-
guerreotypes, and they soon became known all over the world. Only
a few of those made by Daguerre personally, and vouched for as such,

254 COMMERCIALIZATION OF DAGUERREOTYPY

are preserved. One of these was exhibited at the Paris Exposition in
1900 and was later published in the official report. 5 The early da-
guerreotypes were generally preserved in paper wrappings, which
injured the delicate images. As early as 1839 Daguerre protected his
pictures by inserting them in frames or cases under glass.

In his early practice Daguerre knew only of the imperfect fixation
of the daguerreotype with a warm common salt solution, which gave
them a mottled appearance. One of the greatest improvements of the
daguerreotype process consisted in the introduction by Sir John
Herschel 0 of hyposulphite of soda as a fixative. This scientist discovered
the salts of the hyposulphurous acids in 1819 and had already called
attention to the solvent action of hyposulphite of soda on silver chlor-
ide 7 (see British Journal of Photography Almanac , 1931, p. 156).

At that time Herschel associated a great deal with Talbot, who in
the beginning could fix his silver chloride images on paper only very
imperfectly with a solution of common salt. It was Herschel who called
Talbot’s attention to the advantages of hyposulphite of soda and en-
abled him as early as May 1, 1839, to acknowledge the benefits of this
improved fixation. Daguerre soon learned of this and, abandoning his
imperfect method of fixation with a warm solution of salt, immediately
adopted for use hyposulphite of soda, in 1839.

Daguerreotypes were greatly enhanced in beauty and improved
in permanence by being toned in a bath of hyposulphite of soda con-
taining gold chloride. The invention of this gilding process was made
by the French physicist Fizeau, in 1840. 8 This advance was generally
adopted and largely increased the public demand for daguerreotypes.

Fizeau’s fixing bath contained 300 parts of hyposulphite of soda,
1 ,000 parts of water, and one part of chloride of gold. The pharmacists
Mathurin Joseph Fordos and Amadee Gelis, manufacturers of chemical
products at Paris, analyzed the double salt formed by this process, de-
termined its composition, and called it “hyposulphite of gold and
sodium,” later known as “sodium auro-thiosulphate. In the trade it
was called “Sel d’or de Fordos et Gelis,” and subsequently it became
the basis for many of the combined toning-fixing baths of modern sil-
ver printing papers.

In the early years of daguerreotypy, according to the statement of
the inventor, silver-plated copper plates were used and pure iodine
vapors, that is, silver iodide, which confined the art to taking of inani-
mate objects, owing to the necessity for long exposures. Notwithstand-

COMMERCIALIZATION OF DAGUERREOTYPY 255

ing this limitation, the public took an unprecedented interest in the
art of photography.

IMPROVEMENTS IN THE DAGUERRE-GIROUX CAMERA

In 1841 Alexis Gaudin made a very small and handy camera with a
very short focus lens; he also affixed to it a kind of exposure shutter
permitting instantaneous exposure by means of a cloth flap covering
the lens.

The introduction of the tripod for the camera is attributed to Baron
Armand Pierre de Seguier (1803-76) as early as 1839. The announce-
ment of this accessory is found in an annotated edition of the original
pamphlet by Daguerre, published by Susse and Lerebours, October,
1839 (G. Cromer, Revue franpaise de photographie, 1930, p. 154).
Chevalier equipped his camera with a tripod in the same year.

Baron Seguier was the first to recommend, in 1839, a leather bellows
to make the camera more portable. With the same purpose in mind
Friedrich Voigtlander, at Vienna (1841), gave the daguerreotype
camera the shape of a truncated cone. This was one of the first more
convenient daguerreotype cameras built entirely of metal, easily car-
ried, readily taken apart and assembled. The sensitive plate was inserted
in the wide section; in the front was the Petzval portrait lens, and in
the back a focusing lens. The plates were round. The directions for
the use of the Voigtlander small metal camera are interesting. They
read:

Directions for the use of the new daguerreotype apparatus for the making
of portraits, executed according to the calculations of Professor Petzval
by Voigtlander and Son, Vienna, printed by J. P. Sollinger, August 1, 1841.

The person to be photographed must be seated in the open air. For an
exposure by overcast, dark skies in winter 3V2 minutes is sufficient; on a
sunny day in the shade 1 V2 to 2 minutes are enough, and in direct sunlight
it requires no more than 40-45 seconds. The last, however, is seldom em-
ployed on account of the deep shadows necessarily obtained. [[See 5th num-
ber of the Verb. d. n. 6 . Gevo. Verein, Vienna 1842, p. 72.]

This was followed by a variety of differently constructed cameras.

In 1845 Friedrich von Martens, a copperplate engraver in Paris,
invented the first panoramic apparatus for curved daguerreotype plates,
which had a visual angle of 150° ( Compt . rend., 1845). The apparatus
was called “Megaskop-Kamera” or “Panorama-Kamera.” A great dis-
advantage of Martens’s apparatus was the difficulty in the handling of

2 56 COMMERCIALIZATION OF DAGUERREOTYPY

the cylindrically curved plate. The lens was capable of being turned.
Notwithstanding this and other difficulties, some results were obtained,
and one specimen was preserved and was exhibited at the celebration
of the centenary of photography by the Photographic Society of Paris.
The picture represented an extensive view: “Panoramic view of the
banks of the Seine in the direction of the Institute at Paris, 1 844.” This
invention had no significance either for daguerreotypy or the collodion
process. 9 It was not until the invention of the flexible silver bromide
films that the invention achieved the great success which it merits. The
prototype of the Kodak Panoram camera, introduced with commercial
success in 1 900, is easily seen at first sight. The Kodak Panoram camera
permits an instantaneous exposure over an extensive field of vision by
an analogous turning of the lens and by a slit shutter passing in front
of the film. It was first shown at the Exposition in Paris, 1 900 ( Jahrbuch
f. Phot., 1901, p. 159).

As a matter for curiosity we mention that the daguerreotypist Netto
constructed, in 1842, a studio in which the front part of the camera
with the lens was built into the wall between the workroom and the
adjoining darkroom. An illustration of this will be found in Nord.
Tidskr.f.Fot. (1920, p.119).

DAGUERREOTYPY CARICATURED

The degree of enthusiasm awakened by daguerreotypy in the whole
world is shown in a caricature by Maurisset in Paris, published 1839-
40, having as its subject “Daguerreotypomania.” This was reproduced
in Nadar’s Paris-Photographe (1893, p. 486), as well as in Phot. Rund.
( 1 889, p. 1 o 1 ) . The latter journal remarks:

This French pamphlet expresses the accumulated wrath of the artist, wor-
ried over his bread and butter, against the new invention of photography.
In the center is a great bustle and tumult of the crowd from all walks of
life around a studio of adventurers: “Maison Susse freres,” which advertises
portraits in thirteen minutes without sun, “Epreuve retoumee,” “Etrennes
daguerreotypiennes pour 1840,” and “Fenetres a Iouer.” On the first plat-
form we see a real detective apparatus in imaginary action, and beside it
proofs are shown. On the second platform is a larger camera, with an um-
brella and a clock— object doubtful. On the left a pupil of Daguerre’s is in
the act of photographing a dancing girl in a hazardous position, about to
leap onto a tightrope— music and gas lamps, which were a novelty then,
serve to accentuate the effect. In the left foreground a photographer, with

COMMERCIALIZATION OF DAGUERREOTYPY 257

a portable traveling apparatus under his arm, photographs a struggling
child held by mother and nurse. In the right foreground one sees the system
of Dr. Donne, copies on paper, accessories for taking portraits, such as a
headrest, a knee guard, and other imaginable contrivances for keeping the
person from moving. Alongside stands the famous doctor with his magic
wand and directs the ensemble with remarkable dignity.

In the foreground are disposed photographic accessories, such as vapor
boxes and phials, and so forth. For the gentlemen who make their living
from copperplate engraving a stately row of gallows are for hire, and some
of them are occupied. A countless procession of curiosity seekers, as well
as a steam boiler, are reproduced on the upper right of our page. Whether
the circle of dancers pirouetting in front of the steam camera are a prophecy
of the instantaneous pictures of modem times, remains unsolved. Human-
ity is divided, according to the picture, into “daguerreomaniacs” and “da-
guerreotypolators,” let us say, “daguerreocrazed” and “daguerreo-amazed.”
Railroads, novel then, and steamships are not omitted from the drawing;
we see a train and a boat loaded— with cameras only. Factory numbers 200,
250, and 300 are especially emphasized in the picture, even the balloon
photographer is here.

Indeed, photography from a balloon in the air, prophesied by the
caricaturists, was successfully executed by Nadar, in Paris, in 1858.
Many of the other dreams were fulfilled, but photography proved
itself an advantage rather than a detriment to the fine arts.

A caricature of Daguerre is found in the much-sought-after work
Musee Dantan; galerie des charges et croquis des celebrites de I’epoque
(Paris, Delloye, 1838-39). The drawing is by Dantan, Jr.; the wood-
cut, white on black, by Grandville. The bust of Daguerre is on a pedes-
tal which represents the diorama, and its name is on the pedestal as a
picture puzzle.

Another harmless caricature, dating from the early days of da-
guerreotypy (end of 1839) is a lithograph printed by Aubert & Co.,
Paris, and published by them. One may see in this a Daguerre-Giroux
camera in which the picture is looked at from above, reflected by an
inclined mirror on a ground glass.

These caricatures give an idea of the hold daguerreotypy had on the
popular mind.

Chapter XXX. first use of the word “pho-
tography,” march i 4 , i8 39

For a long time the date when the word “photography” was first used
remained obscure. Through the efforts, however, of Dr. Murray, edi-
tor of the Oxford Dictionary and one of the greatest contributors to
the history of the English language, the question was cleared up in
1905. As far as can be ascertained the first use of the word “photog-
raphy” was made by Sir John Herschel in a lecture before the Royal
Society of London, on March 14, 1839. He used there the terms
“photographic” and “photography,” in the present meaning of these
words, in his article “On the Art of Photography; or, The Application
of the Chemical Rays of Light to the Purpose of Pictorial Represen-
tation.” Niepce used the term “heliographic”; Talbot the word “photo-
genic.” Evidently it seemed more appropriate to Herschel to coin the
general term “photography.” In France it was not until May 6, 1839,
that the term “art photographique” appeared in the Compt. rend.,
VIII, 714.

Arago used the word as a matter of course in his report on Daguerre’s
process to the Chamber of Deputies, July 3, 1839. The term is con-
stantly employed in later issues of the Compt. rend., from July to
September, 1839, and became universally adopted. We must therefore
call March 14, 1839, the literary birthday of the word. It is quite cer-
tain that Niepce, Daguerre, and Talbot did not know or use the word.
Talbot lectured on his invention six weeks earlier than Herschel, when
he reported his own investigations, but the word “photography” did
not occur; he spoke only of photogenic drawing. He called his photo-
graphs “Talbotypes” and “calotypes.”

It was found out later that the word “photography” had been used
a few days earlier than by Herschel in a German newspaper.

Professor Erich Stengerhas called attention to this (Brit. Jour., 1932,
p. 577; also Phot. ~Rund., 1932, p. 353). In the Vossische Zeitung of
February 25, 1839, the word “photography” was first used by a con-
tributor in an article on Talbot’s inventions. The writer seemed to
have placed very little value upon the use of this new word, because
he did not sign his full name, but only his initials, “J. M.” He writes
that he used the word “photography” on account of brevity for the
inventions of Daguerre and those of Talbot. This use of the word re-
mained unnoticed for ninety years, until Eduard Buchner, the editor,
called attention to it in the Festival Edition, “Zweihundert Jahre Kul-

SCIENTIFIC BASIS OF PHOTOGRAPHY

2 59

tur im Spiegel der V ossische Zeitung." The writer of the original
article, “J. M.,” remained unknown until Professor Stenger succeeded
in determining that it was written by the Berlin astronomer Johann von
Maedler (1794-1874). Maedler studied natural sciences and special-
ized in astronomy. In 1 842 he induced the banker Wilhelm Beer (the
brother of the composer Meyerbeer) to equip a private observatory in
Berlin, where they collaborated in producing a large map of the moon
(1834-36).

In 1836 Maedler became observator at the observatory in Berlin,
and in 1840 director of the observatory in Dorpat. He wrote many
articles on astronomy and published, in 1872, a Geschichte der Him-
melskunde. He wrote a good many articles on the natural sciences for
the V ossische Zeitung and interested himself greatly in the publica-
tions of Daguerre and Talbot. His article on February 25, 1839, in that
newspaper, therefore, establishes the birthday of the word “photog-
graphy” and that Johann von Maedler was its author.

Of course, it must not be forgotten that the use of the word by an
unknown and anonymous newspaper contributor was not noticed by
anyone, while Sir John Herschel’s mention of it made the word known
to the whole world.

Chapter XXXI. scientific investigation

OF THE CHEMICO-PHYSICAL BASIS OF PHOTOG-
RAPHY

As soon as daguerreotypy became generally known, scientific inves-
tigations concerning it began everywhere. The earliest theory of the
origin of the ability to develop the latent light image 1 on the daguerreo-
type plate was expressed by Arago in 1839 with the publication of the
process in that year. He assumed that silver iodide is reduced in light
to metallic silver which absorbs the mercury vapor, forming the lights
of the image in amalgam, while the unchanged silver iodide is elimi-
nated by the subsequent fixation. N. P. Lerebours reports on this in his
Historique et description de la daguerreotypie (1839).

This chemical theory was opposed in the same year by Al. Donne,
who offered another physical theory. He observed that a silvered plate
subjected to iodine vapor is physically changed under the action of

SCIENTIFIC BASIS OF PHOTOGRAPHY

260

light, suffering a change of structure on its surface and becoming
powdery so that the powder can be removed by gentle rubbing
( Compt . rend,., 1839, XI, 376) . He assumed that the mercury vapor
penetrates the exposed silver iodide layer (which has become powdery
in its consistency) to the metallic silver plate, while the nonexposed
and still coherent silver iodide layer resists the action of the fumes.
Claudet, as well as Gaudin, made similar observations, as Schultz-Sellack
noted later ( Handbuch , 3d ed., 1927, II (3), 6).

In 1842 Ludwig Ferdinand Moser (1805-80), professor of physics
at Konigsberg, brought the so-called breath pictures (“Hauchbilder”)
into prominence. If a coin is placed on a clean glass plate for a few
hours, a picture remains after the coin is removed if one breathes on the
spot. He applied this to daguerreotypy. This demonstrates that many
of the later theories (Hunt and Knorr) were discussed even then, and
this refers also to the subject of “electrography” (Karsten) .

Moser found that the well-polished surface of a glass or metal plate,
when brought into contact with another body, attracts moisture (steam
or breath). Moser assumed that the condensation of mercury vapor
on the exposed daguerreotype plate revealed (developed) a breath
picture (“Hauchbild”) and made the interesting discovery that a
fully exposed daguerreotype plate could be developed with steam; an
image brought out by steam disappears, however, in a very short time.
He did not agree with the theory of a chemical change in silver iodide
(as assumed by Arago) , but with a physical action, according to Donne.
Moser supported his theory with an experiment made by Draper, who
exposed an iodized silvered plate together with moist starch paper to
sunlight; but no trace of liberated iodine could be proven (Pogg.,
Annul, LXV, 190). 2

Very important was the recognition that the latent image on the
daguerreotype plate is destroyed by the fumes of iodine, bromine, or
chlorine and that the developability is thereby lost (Gaudin, Compt.
rend., 1841, I, 1187). This was thoroughly investigated two years
later by G. Shaw and Percy (Phil. Mag., Dec., 1843) . They found also
that a daguerreotype plate on which the latent image had been de-
stroyed by iodine or similar agents was capable of giving a developable
image after re-exposure ( Handbuch , 3d ed., 1927, II (3), 8).

Subsequently scientists abandoned the theory of the physical action
of light, owing to the investigations of Choiselat and Ratel in 1843, 3
and turned to still another theory in favor of photochemical action.

SCIENTIFIC BASIS OF PHOTOGRAPHY 261

These experimenters assumed that the silver iodide loses at first a part
of the iodine in light, forming the hypothetical subiodide of silver
(Ag 2 J), while the iodine photochemically liberated is absorbed by
the underlying silver of the plate. The mercury vapor decomposes not
only the silver iodide (AgJ) but also the subiodide (Ag 2 J) in a differ-
ent manner; the parts of the silver iodide not acted upon by the light
are changed into mercurous iodide and metallic silver by the action
of mercury vapor. The silver subiodide formed during the exposure
forms in contact with the mercurous iodide resulting from the above-
mentioned reaction, metallic mercury and silver, according to the
following equation: zAg 2 J + zHg 2 J 2 = 3HgJ 2 + Hg + 4Ag. The
silver and mercury combine in a white amalgam ( Handbuch , 2d ed.,
1898, II, 11, 32, 1 12). In fixing with hypo the mercuric iodide dis-
solves completely, leaving behind a white silver amalgam in the light
parts; in the shadows it dissolves the mercurous iodide, and only dark,
finely divided silver remains.

We shall not go further into these complicated theories, but will
only point out the historical fact that in 1 843 Choiselat and Ratel es-
tablished for the first time the theory that the latent image consists of
silver subhalide.

The latent image on the daguerreotype plate disappears gradually
when it is kept in the dark, as John W. Draper was probably the first
to observe. This retrogression was investigated by Carey Lea (Phot.
Korr., 1866, III, 129; 1867, IV, 53; Philadelphia Photographer, April,
1866, III, 97), also in pure silver iodide, which was produced by iodiz-
ing silvered glass mirrors ( Handbuch , 1898, II, 85).

And so as early as 1 840 all these theories of the latent light image
obtained with silver halide salts were advanced which kept the photo-
chemists of the nineteenth century busy and are not finally determined
today. In order to complete the record it must be added here that
August Testelin assumed in his Essai de theorie sur la formation des
images photographiques, rapportee a une cause electrique (Paris, 1 860)
that the silver iodide molecules acquire an electric polarity during the
exposure which brings about the precipitation of the mercury vapor
on those parts affected by light.

The procedure during iodizing and developing the daguerreotype
plate was very carefully and scientifically investigated.

Already Daguerre had noticed that the silvered plate, while being
iodized, changed in surface hue to yellow, red, violet, and greenish

262 SCIENTIFIC BASIS OF PHOTOGRAPHY

blue and that, if the exposure is prolonged, the change of color repeats
itself in the same sequence (layers of the first, second, and third order).
Daguerre iodized to gold-yellow (1839) or up to the violet-rose red
of the first order. 4 Jean Baptiste Dumas measured the thickness of the
gold-yellow iodide layer (1839) and found it no thicker than one mil-
lionth of a millimeter. The development of the daguerreotype is ef-
fected, in practice, by the vapors of mercury heated to about 50-60° C.
The microscopically small mercury “drops” which deposit on the parts
of the picture were measured by Brongniart (Paris), who found they
had a diameter of 0.04 millimeter.

The physicist Karl August Steinheil, of Munich, introduced, in 1 842,
the use of cold mercury fumes for the development of exposed da-
guerreotype plates, by placing an amalgamated copper plate close to the
daguerreotype plate. The development required much more time-
several hours— but the result was good, and the mercury particles on
the plate were much smaller than those deposited by hot vapors.

It was found that on pure copper plates (not plated with silver)
which had been subjected to the vapor of iodine, bromine, or chlorine,
light images could be obtained which could be developed by mercury
vapor. Talbot seems to have been the first to discover this, and he,
characteristically, applied in 1 841 for an English patent on it ( Abridge-
ments Br. Pat., 1861, p. 4; Dingler’s Polyt. Jour., LXXXII, 192). At
the same time and independently Kratochwila of Vienna made the
same observation (Dingler’s Polyt. Jour., LXXXI, 149).

Wells also applied for a patent on this ( Abridgements Br. Pat., 1872,
II, 1 21). Talbot also stated that such images on iodized copper plates
could be developed with hydrogen sulphide, without mercury ( Hand -
buch, 2d ed., 1898, II, 56, where other notes on this subject will be
found). It is worthy of notice that Prechtl, director of the Vienna
Polytechnikum, fixed daguerreotype plates which had been normally
developed with mercury vapor in a very dilute solution of ammonium
sulphide, which caused the parts not amalgamated to turn gray (Ding-
ler’s Polyt. Jour., LXVII, 3 1 8). None of these modifications, however,
equaled the results obtained by the original daguerreotype process.

Sir John Herschel broadened the knowledge of photochemical
actions; the results of his investigations were of the greatest importance
in applied photography. In 1840 he examined the behavior of nitrate
and bromide of silver papers toward the solar spectrum. He found that
the image of the chemical spectrum on silver nitrate paper was 1.57

SCIENTIFIC BASIS OF PHOTOGRAPHY 263

times longer than the visible spectrum; on silver chloride paper it was
1.8 times, and on silver bromide paper as much as 2.16 times longer.
After observing this extended sensitivity range of silver bromide, he
declared, even as early as 1840, “we must create a new photography,
of which silver bromide will form the basis.” These important new
publications by Sir John Herschel were entitled: “On the Chemical
Action of the Rays of the Solar Spectrum on Preparations of Silver
and Other Substances, Both Metallic and Nonmetallic, and on Some
Photographic Processes” (Phil. Trans, of the Royal Society of London,
Part 1, p. 1, February 20, 1840) and “On the Action of the Rays of the
Solar Spectrum on Vegetable Colours and on Some New Photographic
Processes,” with Postscript“On Certain Improvements of Photographic
Processes Described in a Former Publication and on the Parathermic
Rays of the Solar Spectrum” (Phil. Trans., June 16, 1842, XII (2), 181,
and Postscript on p. 209, August 29, 1842). In these dissertations
Herschel reported the action of the rays of the solar spectrum on
various silver and iron salts and on vegetable dyes. There is also men-
tioned the bleaching action of light on pigments.

HERSCHEL EFFECT

Sir John Herschel published in the Philosophical Transactions
(1840), an observation which he had made on August 27, 1839, in
which he made known for the first time that silver chloride paper turns
dark in the concentrated light of the solar spectrum, but bleaches
under the oxidizing action of red light. He states that red light, which
is considered inactive, exercises an opposite action to that of blue and
violet light.

Later Draper (1842), Lerebours (1846), and Claudet (1847) found
that this effect of red light also applied to the latent light image on
iodized silver daguerreotype plates and to the development with mer-
cury vapor. The later evolution of these early experiments in this direc-
tion, which extended to collodion and gelatine silver bromide plates,
is dealt with exhaustively in the author’s Handbuch (1891, Vol. I, Part
2 ) and has passed into technical literature. Later investigations of the
Herschel effect are described by Luppo-Cramer in his “Grundlagen
der Negativverfahren” (Handbuch, 1927, Vol. II, Part 1) and in his re-
port at the seventh International Congress of Photography, London,
1928. Another interesting study on the subject by A. P. H. Trivelli is
given in “Communication No. 383,” of the Kodak Research Labora-

264 SCIENTIFIC BASIS OF PHOTOGRAPHY

tories, 1929. Also see the dissertation of Johannes Narbutt, Vber den
Herscbel-Effekt (Giessen, 1930).

The name “Herschel effect,” which was originally used only for
the direct blackening and bleaching process of silver chloride paper,
was subsequently applied in researches on the latent image and the
developing process. The importance of the phenomenon lies in its
application to photography with infrared rays, to the production of
direct positives and duplicate negatives, and to the theory of the latent
image.

In 1 840 Herschel stated: “Immerse an ordinary silver print in a solu-
tion of mercuric chloride. The picture image is completely bleached
out, leaving clean, white paper. If now you immerse this piece of clean,
white paper in a solution of fixing salt (hypo), the picture image re-
appears in all its original intensity.” This is the principle of the so-called
magic photographs, 5 as well as that underlying the intensification of
negatives.

In the second paper mentioned above ( 1 842 ) , Herschel described
for the first time the discovery of the iron printing processes with
ammonio-citrate of iron by both methods, namely, with blue lines on
a white background and white lines on a blue ground (cyanotypy, blue-
print-iron process; Handbuch, 1929, Vol. IV, Part 4). He also in-
vented the “chrysotype process,” which depends on the exposure to
light of ferric salts and the development of the ferro-image with gold
and silver solutions ( Handbuch , 1929, Vol. IV, Part 4).

Herschel did not obtain photographically the Fraunhofer lines of
the solar spectrum. The first to photograph these was E. Becquerel on
daguerreotypes in 1842-43. Draper also worked along these lines and
discovered in 1843 the action of the infrared rays. Stokes, employing
fluorescent substances in 1852, found that quartz transmits most ultra-
violet rays, which led Crookes (1854) to the spectrography of the
ultraviolet with wet collodion plates.

Edmond Becquerel (1820-91) came from a family of celebrated
French physicists. His father, Antoine Cesar Becquerel (1788-1878)
successfully devoted himself to physical and chemical studies. His son
Edmond was born in Paris, March 24, 1820, and died there on March
13, 1891. He worked at the Conservatory of Arts and Trades in Paris
and was an outstanding scientific scholar in the field of photography;
his works are often referred to. His investigations cover many fields
and are important (electric light, galvanism, 0 magnetism, diamagnetic

SCIENTIFIC BASIS OF PHOTOGRAPHY

265

properties, phosphorescence, and so forth). In photographic science his
book La Lumiere, ses causes et ses effets (2 vols., Paris, 1867-68) is of
particular importance.

Edmond’s son, Antoine Henry Becquerel (1852-1925), became in
1892 professor at the Museum for Natural Sciences, Paris, in 1894
Chief Engineer of Roads and Bridges, and in 1895 professor at the
Polytechnical School. His work included among other subjects that on
infrared light and phosphorescence, and he discovered the rays named
after him (uranium rays, Becquerel rays), which are invisible rays
continually emitted by pitchblende that act on silver bromide gelatine
plates or films through the carton and black paper. Further investiga-
tion of this phenomenon led M. and Mme Curie to the discovery of
radium. They found that pitchblende contained substances from which
rays emanate with properties similar to those of the Roentgen rays,
namely, radioactivity. In 1903 M. and Mme Curie, with Henry Bec-
querel, received the Nobel prize for their investigations of radium.

INCREASE IN THE SENSITIVITY OF DAGUERREOTYPE PLATES
BY THE INTRODUCTION OF BROMINE

The most important advance in the progress of daguerreotypy re-
garding their sensitivity to light was made with the discovery that the
complex combinations of silver iodide with silver bromide or silver
chloride, in the form of silver iodo-bromide or iodo-bromo-chloride
of silver, were much more sensitive to light than pure silver iodide; a
discovery of the greatest value, not only in daguerreotypy, but for the
Talbotype and the wet collodion processes of earlier years, as well as
for the gelatine emulsions of today.

The introduction of iodo-bromide by John Frederick Goddard,
London, and Dr. Paul Beck Goddard, Philadelphia ( 1 840) , as well as
that of iodine bromo-chloride at the same time, or perhaps somewhat
earlier, by Kratochwila, in Vienna, is described in the next chapter.

becquerel’s “continuing rays”; secondary exposure

WITH RAYS OF LONG WAVE LENGTH

The discovery of the partly equivalent and partly antagonistic action
of the colored rays of the solar spectrum on photographic silver salt
layers was theoretically, and in some degree practically, important.

Edmond Becquerel seems to have been the first person to observe,
in 1840 ( Compt . rend,., II, 702), that the latent daguerreotype image

2 66 SCIENTIFIC BASIS OF PHOTOGRAPHY

which had been underexposed could be intensified if re-exposed to the
yellow and red rays of the spectrum and then developed with mercury.
The secondary exposure under red glass supplements the original ex-
posure (Becquerel, La Lumiere, ses causes et ses effets, Paris, 1868,
II, 76, 90, and 1 76;. see also the bibliography) . Explaining this phenome-
non, Becquerel called the yellow-red rays continuing rays (“rayons
continuateurs”) in contrast to the primary rays, which excited or pro-
duced the light image and which he called exciting rays (“rayons
excitateurs”).

These phenomena are usually called the “Becquerel phenomena” in

f hotochemistry; they are dependent on the wave length of the light. 7
t is very curious that Moser, who, like all other investigators mentioned
here, concerned himself only with daguerreotypy, opposed the theory
that the red and yellow rays were called “continuing,” and the blue
and violet rays “exciting” in the photographic process. Moser pro-
nounced this classification erroneous and advocated the theory that all
rays, that is, rays of every wave length, are capable of commencing as
well as of finishing the action of the light; and within certain limits he
is correct.

Edmond Becquerel was not alone in his observation, as Eder indi-
cated in 1884 ( Handbuch , 1884, I, 53).

Antoine Gaudin, in 1841, attempted to use the “continuous action”
of the red rays in photography for the purpose of shortening the ex-
posure ( Compt . rend., XII, 862, 1060); Fizeau also recommended a
short exposure for the brominated daguerreotype plates for portraits,
followed by another exposure to the action of “continuous” rays
(Stenger, Wissensch. Zeitung f. Phot., 1930, XXIX, 45).

Fizeau and Foucault 8 described the so-called negative action of cer-
tain light rays very accurately, having placed in the hands of the Paris
Academy a sealed letter on December 9, 1 844, containing their report
on this subject. In their experiments they caused the light of a lamp to
act on a bromo-iodized daguerreotype plate, until it was covered by
the mercury vapor with a uniform white layer. However, before they
subjected the plates to the vapor, they exposed them to the solar spec-
trum. When the plates were subjected to the mercury vapor, two dis-
tinctly different parts of the spectrum were visible. On the one side of
the orange, up to the most refrangible or “actinic” rays, a strong con-
densation of the vapor accrued, while, on the other side of the less re-
frangible rays, and indeed far beyond the red, no condensation was

SCIENTIFIC BASIS OF PHOTOGRAPHY 267

noticeable. It follows that these rays had neutralized the effect cf the
lamp. Foucault and Fizeau therefore call this action negative in contrast
to the positive action of the stronger refrangible rays. If the time of
exposure is lengthened during which the spectrum acts on the plate,
the precipitate extends to the maximum of the negative action. More-
over, it is observed that between the decidedly positive and decidedly
negative acting rays, there exists a class of rays which have sometimes
one and sometimes the other effect, according to the intensity and
length of their action. These rays which are found particularly in the
orange, act negatively when they are weak or when the exposure is
short, but under opposite conditions they give positive results.

Claudet also, in 1847, demonstrated that the red and yellow rays of
the spectrum prevent the action of the other (blue) rays on bromine,
iodine, or silver chloride (daguerreotype plates) and destroy the action,
if it has taken place, so that the image is not developed by the mercury
vapor; later he found 9 that red and yellow rays always exercise a nega-
tive or destructive effect on bromo-iodide or bromo-chloride plates,
but on pure iodine plates they act sometimes in the same ways as do
blue rays and sometimes negatively. Concerning the relative action of
the respective rays, according to Claudet, to destroy the action of white
light which acted for the unit time, red light requires an exposure of
the relative time of 50, orange colored, 15, yellow, 18.

Draper obtained solarization phenomena from G up to the infrared,
with the positive appearance of Fraunhofer’s lines, when he exposed
daguerreotype plates to the spectrum and simultaneously to weak,
diffused daylight . 10

Very important is the discovery of photogalvanic and photoelectric
currents by Becquerel in 1839 and subsequent years. He observed that
when light falls on one of two plates of platinum, gold, or silver that
are immersed in an acid or alkaline bath, a galvanic current will at once
circulate between them. The current is greatly increased when the
silver plates are coated with chloride, iodide, or bromide of silver.

In 1841 Becquerel constructed his “electro-chemical photometer,”
based on the above-described phenomenon; by the use of silver sub-
chloriJe he accomplished with this apparatus photometric readings
which correspond to the sensation caused by light on the retina in the
human eye.

The generation of photogalvanic currents has since become of great
importance in the study of physics and photochemistry. The “photo-

268 SCIENTIFIC BASIS OF PHOTOGRAPHY

galvanic effect” has been usually abbreviated to “Becquerel effect”
(B. E.). This distinct, circumscribed electrode Becquerel effect must
not be confused with the above-mentioned photographic “Becquerel
phenomenon,” which deals with the opposite light action of various
wave lengths on silver halide layers— exciting and continuing action
(“Ober den Becquerel-Effekt,” by Chr. Winter, Zeitscbr. f. physikal-
iscbe Cbemie, 1827, CXXXI, 205).

The action of electricity on daguerreotype plates was investigated
by Daguerre in 1839, by conducting an electric current through the
plate during exposure. He believed the sensitivity would be augmented
by it, but the experiment was without success. Becquerel found, in
1841, that electricity reduces a layer of silver chloride, similar to light,
which was verified by Pinaud. He continued his experiments until 1851
and found that a weak electric spark striking a daguerreotype plate
produced a result which could be developed with mercury vapor
(electrography).

For electrographic moisture pictures by Karsten (1842) and Grove
(1857) and electrographic reproductions of medals on iodized da-
guerreotype plates by Volpicelli in 1857 see Eder, Photo cbemie, 1906,
p.419.

DISCOVERY OF “aTMOGRAPHY” ON DAGUERREOTYPE
PLATES BY J. J. POHL, VIENNA

Dr. J. J. Pohl, late professor of chemical technology at the Technical
High School at Vienna, made, in 1 840, an accidental discovery which
may be regarded as anticipating atmography ( Handbuch , 1922, Vol.
IV, Part 3).

He writes: “Finally, I cannot but add the following remarks. In Feb-
ruary, 1 840, that is, five years before Moser published his discovery of
the so-called ‘invisible light’ 11 I worked in daguerreotypy, which at
that time was hardly known in Vienna, without, however, being able
to obtain favorable results, owing to my extremely limited apparatus.
For the sake of simplicity, I tried the method of iodizing, which, if I am
not mistaken, was only a short time before proposed by Steinheil, using
a wooden slab impregnated with iodine vapors in place of the bulky
iodine box commonly employed. The daguerreotype plate was placed
for this purpose on the board (which had been subjected to iodine
vapors for the usually sufficient length of time), but remained by mis-
take exposed more than half an hour to the action of the iodine. When

SCIENTIFIC BASIS OF PHOTOGRAPHY

269

the daguerreotype plate was removed, it showed, much to my surprise,
instead of the normal uniform gold-yellow coloration, a perfect and
sharp picture of the fibrous structure (skeleton) of the wood of which
the board was made, in a dark violet color. I took the opportunity to
show this picture, which appeared in the manner related above, to sev-
eral persons, but in vain, for none could give me a satisfactory explana-
tion of the circumstances surrounding its origin; the picture remained
almost unchanged for three months, kept in a dark place, and was finally
deliberately destroyed.”

DISPARITY OF OPTICAL AND CHEMICAL LUMINOSITY

While making photometric researches with various sources of light
(electric arc light, calcium light, and sunlight) using daguerreotype
plates, the French physicists Fizeau and Foucault observed that the
chemical action of light is in no manner proportionate to its optical
brightness ( Annal . chim. phys., 3. ser., XI, 370).

PONTON, TALBOT, AND HUNT

In order to complete the record of the position of photography at
this time, it is necessary to state that Ponton discovered the sensitivity
to light of paper impregnated with potassium bichromate in 1839 and
that Talbot discovered that a mixture of glue and bichromate became
insoluble by the action of light ( Handbuch , 1926, IV (2), 359).

We must not forget to record R. Hunt’s numerous investigations
of light-sensitive substances in the solar spectrum and his work, Re-
searches on Light (London, 1844; 2d ed., 1854), in which he described
the results of his experiments and recorded many new observations.

We conclude this article dealing with the painstaking observations
of the experimenters of that period, by pointing out that these results
obtained in the studies of daguerreotypy have in a large measure been
found to apply to the collodion process and to the modem emulsion
plates.

PHOTOGRAPHING THE SUN, MOON, AND STARS

Dr. John W. Draper (1811-82) was an indefatigable investigator
in the field of scientific photography. While Daguerre, in 1839, recog-
nized the photographic action of moonlight on his iodized silver plates,
as Arago emphasized in his report, it was Draper who was the first to
produce distinct photographs of the moon in America (1840).

SCIENTIFIC BASIS OF PHOTOGRAPHY

2 7°

Draper obtained this photograph, measuring about 25 millimeters
(0.98 of an inch), by exposing for twenty minutes. (A previous trial
by Daguerre was unsuccessful). His son, Dr. Henry Draper (1837-82)
was later one of the pioneers in the field of astrophotography. He
occupied himself especially with the photography of the Orion neb-
ulae and produced a photograph of it on September 30, 1880, on
collodion plates. A better result was obtained by him March 14, 1882,
by exposing 1 37 minutes.

Fizeau and Foucault photographed the sun on a daguerreotype plate
April 2, 1845, at the request of Arago. 12 In 1845 Fizeau and Foucault
endeavored to make exposures of the eclipse of the sun; in 1851 Dr.
Busch, in Konigsberg, made daguerreotypes of the total eclipse, in
which the protuberances were indistinctly visible.

The first photographs of stars were produced by W. C. Bond, in
Cambridge, Mass., on July 17, 1850, when he obtained a photograph
of some of them.

Later, Warren de la Rue, in particular, occupied himself with celes-
tial photography. This prominent man, who started as a bookbinder,
from 1862 was one of the largest paper manufacturers in London and
owned large electrogalvanic works. He was the first to produce vege-
table parchment, and he practiced celestial photography with ex-
traordinary success. In 1852 he made exposures of the moon on collo-
dion plates; in 1 856 he photographed the sun by instantaneous exposure,
followed in 1858 by Jupiter’s photographs. Foye also used a similar
apparatus with an instantaneous shutter, such as De la Rue employed
when photographing a solar eclipse ( Revue des sciences phot., 1905,
p. 240). Here must also be mentioned the American physicist Lewis
Morris Rutherford (1816-92), who in 1864 made photographs of the
Pleiades with wet collodion plates and a specially corrected lens.
Rutherford constructed in 1 864 the first telescope (11% inches aper-
ture) corrected for photographic rays and made the finest diffraction
gratings obtainable prior to those of Rowland.

He photographed, in 1 848, an eclipse of the moon, and later turned
to astronomy and spectroscopy. In 1866 he made a report to the Vienna
Academy on the photography of the moon and on the solar spectrum
(also Pogg., Annal.).

Gould, Pickering in his Stellar Photography (Boston, 1886), and
others also interested themselves in astrophotography.

DAGUERREOTYPE PORTRAITS

* 7 »

ENLARGEMENTS

The first mention of an enlarging process is probably to be ascribed
to Professor Draper, who wrote in 1 840, in the American Repository
of Arts, “Exposures are made with a very small camera on very small
plates. These are subsequently enlarged to the required size in a larger
camera on a rigid stand. This method will probably contribute very
much to the practice of the art” (Phot. Archiv, 1895, p. 297; compare
with Draper’s collected works). The daguerreotype was, however,
much less suitable for the enlargement process than the invention of
Talbot.

Chapter XXXII. the first daguerreo-
type PORTRAITS; EXPOSURES REDUCED TO SEC-
ONDS

The comparatively feeble light-sensitivity of the pure silver iodide
which Daguerre used in his process demanded lengthy exposures, and
the slow lenses available in France at that time offered no help in short-
ening the exposure. It was on account of the prolonged exposures
necessary that portraits were not at first attempted, even Daguerre
confined himself to pictures of landscapes, architectural subjects, and
the like.

In Arago’s report the taking of portraits was not mentioned, nor
were there any portraits among the early daguerreotypes sent by Da-
guerre to the heads of European governments. Elsewhere, however,
especially in America, where the keenest enthusiasm was aroused by this
new method of taking pictures, many attempts were made to apply
the process in portrait photography. In 1839 the improvements after-
ward introduced into the daguerreotype process, permitting of shorter
exposures, were unknown, but in the autumn of that year Professor
John W. Draper, in New York, 1 made the first photographic portrait
on a daguerreotype plate, giving an enormously long exposure. The
subject of the portrait, Draper’s assistant, powdered his face with flour
and sat in front of the camera for a half hour facing the sunlight. 2

Sir David Brewster, in the Edinburgh Review, January, 1843, states
his belief that Draper was the first to take portraits by Daguerre’s pro-

DAGUERREOTYPE PORTRAITS

272

cess, which no one considered possible, since portraiture was not men-
tioned in the reports of Arago and Dumas on the invention of dagurreo-
typy.

A portrait made in New York with wet collodium showing the cus-
tomary style of posing at that time, pictures Professor John W. Draper
twenty years after he made the first daguerreotype portrait of his
assistant. A portrait of Draper from an etching was procured by Eder
for the Graphische Lehr- und Versuchsanstalt in Vienna (Inventory
No. 538).

In 1 839, at the same time when Draper was there, there lived in New
York a gifted gentleman— one who had a remarkable career. This was
Samuel Finley Breese Morse, who had already achieved fame by the
invention of the Morse telegraph and the telegraph alphabet named
after him; he also took an interest in daguerreotypy. [Dr. Eder wrote
to the translator in his 25th letter, March 21, 1932,]]

1 am very much interested in your historical study on page 359 and 360
Eof my Geschicbte ] regarding Draper. You have evidently found in New
York better sources than I possessed. Your remarks are very exact and
appropriate. Please work up the whole matter regarding Morse, Draper,
etc., as well as Cornelius, independently and add to the American edition
the results of your own investigation.

[(The section immediately following has been rewritten by John A.
Tennant, New York City.]

Morse visited Paris in 1838 to introduce his system of telegraphy
in France. During the winter of 1838-39 he met Daguerre, who invited
him to his Diorama studio and there exhibited and explained his in-
vention of the daguerreotype, at that time held secret and known only
to Arago, with whom Daguerre was negotiating the sale of the inven-
tion to the French government. The probable date of this meeting
of Morse and Daguerre was January or February, 1839, and the two in-
ventors became warm friends.

Writing to his brothers in New York on March 9, 1839, Morse re-
ports Daguerre’s discovery to them and in explanation of his great
interest in it says: “You may recall experiments of mine at New Haven
(Yale College) many years ago, when I had my painting room next
to Professor Silliman— experiments to ascertain whether it were pos-
sible to fix the images of the camera obscura. I was then able to produce
different degrees of shade on paper dipped into a solution of nitrate of

DAGUERREOTYPE PORTRAITS

273

silver, by means of different degrees of light, but finding that light
produced dark, and dark light, I presumed the production of a true
image to be impracticable and gave up the attempt. M. Daguerre has
realized in the most exquisite manner this idea.”

In this remarkable passage, hitherto unnoticed by historians of pho-
tography, we learn that the American Morse had conceived and ex-
perimented in the idea of fixing the camera obscura images by the
action of light about 1812— in the same year that Nicephore Niepce
began his experiments and twenty years before Fox Talbot first at-
tempted to fix the images of the camera obscura on his return from
Italy in 1834.

Morse returned to America April 15, 1839. In May of that year he
wrote Daguerre concerning his (Daguerre’s) election as an honorary
member of the National Academy of Design, at New York, and offered
to promote an exhibition of the daguerreotype in that city if Daguerre
would co-operate. To this Daguerre replied, acknowledging the honor
conferred upon him by the National Academy, but regretting that his
negotiations with the French government, then proceeding, made it
impossible for him to attempt an exhibition in New York as proposed.

As soon as the publication of the process of daguerreotypy became
known in America (August or September, 1839) Morse had the neces-
sary apparatus constructed and began experimenting with the process. 3
His first attempt was to secure a picture of the Unitarian Church visible
from the window of his room at the University of New York, where
he was professor of drawing at the time. This was in September, 1839,
and the exposure required to secure the picture was about fifteen
minutes. Immediately thereafter Morse associated himself with Dr.
John W. Draper, then professor of chemistry in the university, who
was experimenting with daguerreotypy with considerable success. It
seems that both Morse and Draper attempted photographic portraiture
in those early days, having a studio together for that purpose on the
roof of the university. The dispute as to whether Morse or Draper
made the first portrait, often mentioned in the photographic literature
of that period, seems to be conclusively settled in the life of Morse
by his son (1914), where we read (page 146), “It was afterwards es-
tablished that the honor must be accorded to Professor Draper, but I
understand it was a question of hours only.”

In 1 840 Morse made the first group photograph, the subject being
his class of 1810 at the reunion at New Haven (Yale) in that year.

DAGUERREOTYPE PORTRAITS

2 74

Soon after this time Morse abandoned his photographic experiments,
to give his remaining years to the telegraph.

The historically documented description of the first portrait photo-
graphs by Draper became confused when, at the Chicago World Fair
in 1893, the portrait of Dorothy Catherine Draper, the sister of John
W. Draper, was exhibited. The lady, eighty-seven years old, was alive
at that time ( Jahrb . f. Phot., 1894, p. 384). This portrait was labeled:
“This is the first sun picture of a human countenance ever made, taken
by John W. Draper, in 1 840, on the roof of the New York University.”
It is also reported that it was produced in 1840 (J. F. Sachse, Jahrb. f.
Phot., 1894, p. 257). This must be an error, because the proofs can be
adduced that Draper, in the autumn of 1839, took the portrait of his
assistant in full sunlight, 4 and it is said that this daguerreotype is still in
existence (J. Werge, The Evolution of Photography, 1890, p. 108).

About the same time (Sachse claims it was even before Draper,
which, however, is incorrect), namely, in the autumn of 1839, Joseph
Saxton, in Philadelphia (with the assistance of Robert Cornelius),
made experiments in daguerreotypes {Jahrb. f. Phot., 1894, p. 257).
He was employed at the U. S. Mint and was a member of the American
Philosophical Society, in Philadelphia. The first daguerreotype made in
America by Joseph Saxton, from the window of his workshop in Octo-
ber 16, 1839, is reproduced by Julius F. Sachse, “Philadelphia’s Share
in the Development of Photography,” in Journal of the Franklin In-
stitute, April, 1893, Philadelphia.

Cornelius attempted to take his own picture in November, 1839,
with the lens of an opera glass as objective. He placed the camera on a
chair in bright sunlight. After focusing sharply and having inserted
the iodized silver plate, he removed the lens cap and quickly seated
himself on a chair in front of the camera. After about five minutes he
jumped up and covered the lens. The developed plate showed the image
of a man.

This is not only the first self-portrait, but also one of the earliest
portraits of a human being made by the action of light. The body is
portrayed off the center of the plate, because Cornelius did not seat
himself properly on the chair. This picture was submitted to the Ameri-
can Philosophical Society on December 6, 1839, as is recorded in the
proceedings of that society. That this self-portrait was the same picture
that was exhibited at the meeting is certified by Cornelius himself (who

DAGUERREOTYPE PORTRAITS

*75

died i n 1 89 3 , at the age of 8 5 ), as well as b y several living witnesses who
were present at the meeting.

Cornelius was also the first to open a studio for portrait photography,
in 1 840. The light was concentrated by a series of reflectors, and blue
glass was interposed to soften it. The exposure was one minute, and the
price was five dollars for each portrait. Portraits were made only on
bright days. The work of Cornelius is described in the Proceedings of
the American Philosophical Society, March 6, 1840.

£End of section by Mr. Tennant.]

FURTHER DEVELOPMENT OF PORTRAIT PHOTOGRAPHY BY INCREASED
SENSITIVITY OF DAGUERREOTYPE PLATES

Under the conditions described, the time of exposure in the begin-
ning of daguerreotypy was prolonged, and this delayed the progress
of the art of photographic portraiture. There was need for further
basic inventions, both in physics and in chemistry. The only way to
increase the sensitivity of daguerreotype plates was by departing from
the pure silver iodide coating of Daguerre and introducing combined
halide compounds of silver, for example, bromide or iodo-chloride of
silver. The credit for these investigations belongs to J. F. Goddard, in
London, Fr. Kratochwila and the Brothers Natterer, in Vienna.

For the increased luminosity of the photographic lens we are in-
debted to the gifted mathematician Professor Petzval, in Vienna, the
inventor of the portrait lens. The success of portrait photography is
closely interwoven with the name of Petzval; it was he who stimulated
its progress almost within a year or two after daguerreotypy was made
public.

It was John Frederick Goddard, lecturer at the Adelaide Gallery in
London, 5 to whom is due the discovery that the sensitivity of da-
guerreotypes is increased by the use of bromine in combination with
iodine in place of chemically pure iodine vapor.

He was the first to publish the use of bromine in daguerreotypy, as
he did in a short letter, dated December 12, 1840, addressed to the
Literary Gazette. He therein reported a considerable increase in the
sensitivity of daguerreotype plates by the combination of bromine and
iodine. The honor of the introduction of bromine in photography
Goddard must share, however, with Franz Kratochwila, who, in Vien-
na, September, 1 840, invented the same process 0 and published it in the
Wiener Zeitung on January 19, 1841.

276 DAGUERREOTYPE PORTRAITS

Kratochwila’s observation showed that an iodized silver plate gained
at least five times in sensitivity if subjected to a mixture of bromine and
chlorine vapors containing at least 50 percent bromine. He obtained
daguerreotypes by exposures of a few seconds and showed them in
September, 1840, to Professors Liebig and Wohler, who expressed their
approval. By the use of Petzval’s lens he was able to make portraits on
cloudy days in eight seconds. He expressed the hope that “the boldest
dream of producing an instantaneous photograph of even a crowded
street might one day be fulfilled.” 7

The contribution Kratochwila made by introducing bromine into
photography seems to have remained unknown to my predecessors in
the writing of the history of photography. For instance, W. J. Har-
rison, in his History of Photography (Bradford, 1888), mentions only
Goddard. Without doubt Kratochwila had shown his iodo-bromo-
chloride plates to prominent experts earlier than Goddard showed his,
but the latter made the subject public earlier in the journals. Therefore,
to Goddard is due the merit for the first publication, although Kra-
tochwila carried out his experiments with bromine earlier and had
demonstrated to a closer circle that not only bromo-iodide and bromo-
iodo-chloride but also iodo-chloride was used to make daguerreotype
plates more sensitive than is possible with iodine alone. Iodo-chloride
was first mentioned by Claudet in May, 1841 (Dinglcr’s Polytechn.
Jour., LXXXI, 149), but he did not recognize the sensitivity of bromo-
iodide in daguerreotypy. On June 1 o, 1 841 , Claudet read a paper before
the Royal Society (Phil. Mag., 1841) in which he emphasized the
greater sensitivity of bromo-iodide and gave the exact composition of
these preparations, on which so much depends.

The brothers Johann and Joseph Natterer, in Vienna, 8 in 1840-1841,
increased the sensitivity of daguerreotype plates by using a mixture of
iodine, bromine, and chlorine to such an extent that with a Petzval lens
they obtained photographs in less than a second, as confirmed by Berres
(Dingler’s Polytechn. Jour., 1841, LXXXI, 151).

Joseph Natterer, bom in Vienna May 23, 1819, showed his love for
the natural sciences, which was prominent in the whole Natterer fam-
ily, and with his brother Johann worked experimentally with da-
guerreotypy. In the memorable year 1849 he earned the right to lasting
memory, when by his energetic interference with the fanatic Viennese
mob, misled by emissaries, he saved the statue of the Emperor Francis,
in the inner court of the palace, and the Museum of Natural Sciences

DAGUERREOTYPE PORTRAITS

277

from destruction. In 1855 he traveled to Nubia and Central Africa, and
in 1858. returned, bringing with him a number of wild animals for the
imperial menagerie. After some time he returned again to Africa, where
he became Austrian consular agent at Khartoum. He accumulated a
considerable fortune there and expected to return to Europe to devote
himself entirely to science, but he died in Khartoum on December 17,
1862, where in 1867 his brother erected a monument in the cemetery.

One of the original daguerreotypes 0 taken by the Brothers Natterer
in the summer of 1841 shows a crowd assembled in the Emperor Joseph
Place, Vienna. The second one, taken near by, shows a rather poorly-
defined picture of mounted police who were standing still; the exposure
was probably not more than one second. These two specimens, not-
withstanding their shortcomings, were probably the first photographs
of street scenes obtained with an exposure of one second or less. The
opinion that these views, dating from the beginning of photography,
represent the first instantaneous exposures is supported by the fact that
the earliest example of “instantaneous photography” which could be
procured by the “Committee of Installation” for exhibition at the
“Musee Retrospectif (Photographic) ,” at the Paris Exposition of 1900,
to which committee all early photographic documents of the history
of photography in France were accessible, was dated October, 1841. 10
It was a daguerreotype of the “Pont Neuf.” This denies all claims to
priority to those publications which deal with halogen mixtures of
iodine, bromine, and chlorine. 11

Professor Berres of Vienna, in his publication of the Natterer proc-
ess in the Wiener Zeitung (March 24, 1841, p. 610), reports that the
Brothers Natterer had photographed a copperplate engraving by the
light of two oil lamps after an exposure of thirty-five minutes on iodo-
chloride daguerreotype plates, while this could not be accomplished
with iodide plates. This seems to indicate that the Brothers Natterer
also made the first photographic reproduction by ordinary lamp light.

CORRECTION OF FAULTY STATEMENTS ON THE INVENTION OF THE USE

OF BROMINE, IODINE, AND CHLORINE VAPORS FOR DAGUERREOTYPE

PLATES

Potonniee, in his Histoire de photographie (1925), prints a chro-
nology of the use of vapor for daguerreotype plates, but it is incorrect
and has been criticized by this author ( Jahrbuch f. Phot., XXX, 50) .

Potonniee, on page 220 of his book, gives the following chronology

278 DAGUERREOTYPE PORTRAITS

of the invention of sensitizing of daguerreotype plates: Goddard intro-
duced bromine, December, 1839. (This should read December, 1840,
Eder.) Claudet used “iodo-chloride” at the end of 1840. Potonniee
omits documentary evidence. Biot used iodo-bromide, January, 1841.
Gaudin made instantaneous exposures of the Pont Neuf in Paris on
daguerreotype plates in October, 1841.

Now, it has been pointed out that the Austrian amateur Franz Kra-
tochwila is entitled to a large share of the merit for the important intro-
duction of bromo-chloride, since prior to Goddard he had presented
effective results of this sensitizing method, in September, 1839 to
Professors Liebig and Wohler, 12 in the shape of portraits he had ob-
tained in a room with a Petzval lens, although it was not until January
19, 1840, that he wrote of it in the Wiener Zeitung, that is, of the
fuming of iodized plates with iodine and bromine.

In December, 1 840, Goddard published his observation of the favor-
able effect of bromine alone on the sensitivity of daguerreotype plates,
as pointed out in the above-mentioned report. 13

Kratochwila was also the first to introduce the use of chlorine vapor
in addition to that of bromine. Potonniee’s statement that iodo-chloride
was first introduced by Claudet “at the end of 1 840” is not documented;
it seems, moreover, incorrect, because Claudet’s publication on iodine
chloride did not take place until May, 1 841 .

The Brothers Natterer, who in 1841 made instantaneous exposures
with daguerreotyp'e plates in Vienna and in the summer months, as is
quite evident from the position of the sun, are also thrust aside by
Potonniee in favor of Gaudin, who made an instantaneous exposure in
Paris, October, 1841. In justice, at least equal credit should have been
accorded. In addition, Potonniee passes over in silence the fact that
Gaudin was able to obtain his instantaneous exposures only with the
aid of Petzval’s portrait lens.

Errata which should be corrected in Potonniee’s text: “Natterer”
instead of “Matterer,” on pp. 220 and 240, and on pp. 225 and 259;
“Le Gray” instead of “Legray”; “Balard’ instead of “Balart,” p. 220;
“Reisser” instead of “Reiser.”

Chapter XXXIII. the daguerreotype

PROCESS IN PRACTICE

In the early days of daguerreotypy, according to the instructions of
the inventor, the work was done with silvered copper plates and pure
iodine vapors and with only the slow single Chevalier lenses at that
time available. The photographer of 1839 was limited to taking pictures
of inanimate objects, owing to the necessity for long exposures (see
photochemical advances in shortening of exposures) . Notwithstanding
this limitation, the interest of the public was unprecedented.

As early as the end of 1839 traveling daguerreotypists could be en-
countered, making photographs of architectural subjects and of land-
scapes. One of the first of these traveling photographers was the French
painter of battles, Horace Vemet (1789-1863), who as early as Novem-
ber, 1839, made photographs in Malta and Smyrna, together with
Adolphe Goupil (1806-1893), and who in 1840 made professional
photographs for the illustrated book of travels Excursions daguer-
riennes, which among other illustrations contained prints from etched
daguerreotype plates. 1

Baron Gros, a successful amateur in the new art, took a complete
daguerreotype outfit on a diplomatic mission to Greece and returned
with a rich collection of views of the ruins of classic antiquities. At
about the same time a certain Titereon photographed the nomadic life
of the Mexican Indians, as reported by Ernest Lacan in his Esquisses
photographiques a propos de P Exposition universelle et de la Guerre
d'Orient, Paris, 1856, fFr. Wentzel, Phot, lnd., 1926, XXIV, 1219).

It is easily understood that professional photography developed es-
pecially in Paris. The first daguerreotype of a crowned head is that of
King Louis Philippe of France, which Daguerre himself made in 1840.
It was not until many years later that the historian Esnault recovered
it in the Touraine and presented it to the Paris Museum.

A great number of French daguerreotypes, up to the largest sizes,
were exhibited in Paris at the time of the Centennial Celebration of
Photography, of which a record is given in the Bull.Soc. franp. d. phot.
(October, 1925, 3 ser., XII, 285).

As a natural consequence it was Paris that applied photography in
the arts and crafts, and the manufacture of apparatus and accessories
of all kinds was evolved and largely developed there. As early as the

28 o

DAGUERREOTYPY IN PRACTICE

forties Paris became the Mecca for photographers and the center of
the photographic industry. Large and luxurious portrait galleries were
opened, industry applied photography in all its branches, and techni-
cal experts devoted themselves to the development of the new science.

DAGUERREOTYPE STUDIOS IN ENGLAND

The first daguerreotype studio was opened in London, in 1840, by
Beard and Claudet (Brit. Jour., 1912, LIX, 930).

INTRODUCTION OF THE DAGUERREOTYPE PROCESS IN VIENNA

Daguerreotypy was publicly made known in Vienna earlier than
in any other German-speaking country. Daguerre’s gift to the Emperor
of Austria and Prince Mettemich of two of the first daguerreotypes
has been mentioned earlier. In order to make the public acquainted
with this new and marvelous invention, these two pictures were exhi-
bited in 1839 at the Austrian Imperial Academy of the United Fine Arts
in Vienna. We have also related how fully the Emperor and his chan-
cellor appreciated the invention and the honors conferred upon Da-
guerre.

AUSTRIA AND OTHER GERMAN-SPEAKING COUNTRIES

In the German-speaking countries it was Vienna which developed
as the center of progress in daguerreotypy. This applies as well to the
increase in sensitivity of daguerreotype plates as to the epoch-making
invention of the Petzval lens. The latter excelled the products of op-
ticians everywhere and made portrait photography possible.

When Daguerre’s discovery was reported at the public session of
the Paris Academy of Sciences on February 7, 1839, the eminent Aus-
trian physicist Andreas Freiherr von Ettingshausen (1769-1857) hap-
pened to be in Paris. He became professor of mathematics and physics
at the University in Vienna and was instructed by Daguerre in his in-
vention. On his return to Vienna he was therefore in a position to dis-
cuss intelligently the new sensation that agitated the scientific world
and to lecture before the government, his friends, and others interested
in the new invention. The Wiener Zeitung and other German journals
printed the Paris sensation two weeks later. The director of the Poly-
technic Institute in Vienna, Johann Joseph Ritter von Prechtl (1778-
1854), 2 ordered practical tests to be made and advised Anton Martin
(1812-1882), of the Polytechnic Institute, to investigate the new proc-

DAGUERREOTYPY IN PRACTICE 281

ess further. Martin succeeded, in the summer of 1839, in producing
satisfactory daguerreotypes.

Anton Martin devoted himself to the study of physics and chemis-
try, became assistant in the department of physics at the Polytechnic
Institute in Vienna, transfered later to the library of the institute, was
elected a member of the trade association, founded in 1 839. In the same
year he took up the work of daguerreotypy, in which he used an appa-
ratus constructed by the optician Plossl along the lines of Daguerre’s
camera. In 1839-1840 he confined himself to photographing inanimate
objects. He was in constant contact with Ettingshausen and Petzval,
and at the request of Professor Petzval he produced, in May, 1 840, the
first portraits with the double lens invented by Petzval. He was also
the author of the first German textbook of photography and published
numerous articles on photography and electrotypy, as well as a text-
book on physics. He was the first president of the Photographic Society
of Vienna.

A small edition of Martin’s biography by Dr. A. Bauer and J. M.
Eder was printed at the Graphische Lehr- und V ersuchsanstalt in 1921.
Other biographies in this series have dealt with Schulze, Kampmann,
and Klic.

At the same time other Viennese took up daguerreotypy, among
them Endlicher, Beck, August Neumann, and others; they generally
used cameras constructed by themselves. The well-known optician
Simon Plossl, in Vienna, was of great assistance; he constructed lenses
for Daguerre’s camera, with improved radius of curvature of the lens,
without, however, attaining a greater light intensity. Following the in-
vention of the rapid portrait lens by Petzval ( 1 840), an enormous boom
started everywhere, especially in Vienna, where Voigtlander made the
first double objective of this kind. It was the possibility, created by this
lens, of making daguerreotype portraits with short exposures from
which the increased interest by the general public in photography may
be dated. In September, 1839, several of the original daguerreotype
cameras, with accessories, were sent to Vienna by Giroux et Cie., of
Paris, and quickly sold.

The Oesterreichische Zuscbauer of December 16, 1839, announced
that the Parisian apparatus, which at first was sold for 400 francs, “now
costs only 80 francs.” Several advertisements indicate how the photo-
graphic industry grew there. It was announced that the apparatus con-
structed in Vienna was perfect, and it was stated that the price of a

282 DAGUERREOTYPY IN PRACTICE

camera, with both iodizing and mercurizing boxes, in addition to two
silver plates and chemicals, was 45 “Gulden Conventionsmiinze,” 3
while the price of the Paris apparatus, with duty, would be 60 florins.
There are also advertised the names of a “mechanicus” and a university
technician who made equipment and sold it direct to the user, with the
advertisement of a firm furnishing silvered copper plates.

As in other large cities, there soon appeared in Vienna studios for
daguerreotypy, but the real advance started with the invention of the
Petzval portrait objective; daguerreotypes had been made in courtyards,
in the open streets, but very seldom in a professional studio. One of
these studios was opened by Karl Schuh at his residence, and there
congregated from 1840 to 1842 a circle of scientists and others inter-
ested in daguerreotypy, such as Ettingshausen, Petzval, Dr. Berres,
the Brothers Natterer, Kratochwila, Voigtlander, Waidele, Prokesch,
Reisser, Schultes, and, of course, Martin. Regular meetings were held
there, and Martin relates that each participant brought with him practi-
cal proofs of his experiments, which furnished abundant subjects for
discussion. These meetings were the beginning of the Photographic
Society of Vienna.

Schuh was well acquainted with the professors of the university,
who offered him the opportunity to give experimental demonstrations
of the hydro-oxygen microscope of Plossl in the large hall of the uni-
versity during 1840 and subsequently. These demonstrations were
advertised regularly in the official Wiener Zeitung. Schuh’s versatile
enterprise afterwards led him to erect a factory for galvanotypy. He
died in 1863.

Another well-known daguerreotypist of those days was Martin
Theyer, who, with his son, was interested in painting, daguerreotypy,
and copper-plate engraving. A daguerreotype by Martin Theyer (size
514 x 7(4 inches; subject, landscape) was bought for 15 florins C.M.
and is preserved in the collection of the Technical High School,
Vienna (Phot. Korr., 191 1, XL VIII, 639).

The Vienna opticians Rospini and Waldstein 4 took up the exploita-
tion of stereoscopic photography, which was first applied to daguerreo-
typy about 1 845 in France, and made it commercially useful. These
stereo-daguerreotypes were often colored. The stereo-daguerreotype
was fastened on one of the inside covers of the case, while the opposite
cover had placed in it the two small lenses through which one observed
the picture. The author was fortunate in being able to acquire examples

DAGUERREOTYPY IN PRACTICE 283

of these stereo-daguerreotypes, and he added them to the collection
of the Graphische Lehr- und Versuchsanstalt (see Eder and Kuchinka,
“Die Daguerreotypie,” Handbuch, 1927, Vol. II, Part 3).

The intensive pursuit of and the great public demand for photo-
graphs brought into being, about 1840-1842, a horde of itinerant
photographers, who, equipped with a camera and a Petzval-Voigt-
lander portrait objective, set out on their travels.

One of these itinerant photographers, Reisser, a Viennese, when
passing through Linz (capital of Upper Austria) photographed (1841
or 1842) the festival presentation of the colors to a regiment. In this
picture the regiment standing in square formation, the crowds of on-
lookers, windows and balconies decorated with rugs and bunting, and
every window occupied by people, as well as the brilliant, uniformed
reviewing party in the center of the square, were all reproduced per-
fectly. In a very short time Reisser made fourteen exposures of the
scene. This number of exposures in so short a time was possible only
because Reisser used two cameras and had prepared and kept at hand
the required number of ground, polished, and iodized plates in separate
tightly closed brass holders. His exposures lasted one second in good
light, three to ten seconds when it was cloudy, and he also made suc-
cessful photographs indoors. His pictures met with such general ap-
proval that he was permitted to photograph the Royal Bavarian family
at Munich, the Queen of Greece, and several celebrated artists and
scientists. Reisser made daguerreotypes on an extended student trip in
Germany, France, and England ( Frankfurter Gewerbefreund, 1842,
p. 177; Phot. Korr., 191 1, p. 639).

The Viennese painter and daguerreotypist Josef Weninger was
the first itinerant photographer to travel to Dresden, Leipzig, Ham-
burg, and into the northern countries. Wherever he went, he spread
the news of the new invention and gained pupils for it. Weninger’s
missionary trip in Sweden and Norway on behalf of the new art is
described by Helmer Backstrom (Phot. Korr., 1922, p. 6).

According to Dr. Friedrich Schulze, director of the Historical Mu-
seum of the City of Leipzig (Phot. Chronik, 1918, p. 75), Weninger
produced his pictures in the shade with very short exposures, pre-
sumably in a closed room. This is apparent also from his advertisement
of January 23, 1842, which emphasizes his independence of the weath-
er. That the photographer of those early years could not resist the
temptation to surround himself with the glory of having to combat the

284 DAGUERREOTYPY IN PRACTICE

difficulties of the process is easily understood; but Weninger kept with-
in the bounds of truth and plausibility when he remarked, after having
given a demonstration of daguerreotype exposures during an explana-
tory lecture before the Society of Arts and Trades, that it was neces-
sary for a successful result with his apparatus to possess “not alone
extraordinary knowledge and experience in chemistry, owing to the
peculiar conditions surrounding the use of chlorine and iodine, the
use of mercury vapors, and the manipulation necessary for the washing
of the plates in the solution of common salt, but also an appreciation
of the art of portrait painting in order to bring out the natural pose
and facial expression of the sitter.” In consequence of having met these
indispensable requirements, Weninger selected for himself the title
“portrait painter and chemist of Vienna.”

In the Tageblatt of January 23, 1842 (No. 23, p. 174) appears the
following advertisement:

Portraits by Daguerre's Process

in 20-40 seconds, according to the latest and improved method!

Josef Weninger, portrait painter and chemist of Vienna, has the
honor respectfully to announce that he is ready to produce during
his stay here portraits after the manner of Daguerre, and in fact,
according to the latest Viennese inventions. The weather in no
way interferes with the production, and a most striking likeness
is guaranteed. Price one Louis d’or (20 gold francs).

PHOTOGRAPHY IN GERMANY

Karl August Steinheil, the celebrated physicist and expert in elec-
tricity of Munich, who was the founder of the optical establishment
named after him, is said to have been the first who produced daguerreo-
types in his laboratory, as soon as the process became known in Ger-
many.

We have a very detailed account of the beginning of photography in
Berlin in Fritz Hansen’s report Die ersten Anfange der Photographie
in Berlin, published on the occasion of the fiftieth anniversary celebra-
tion of the Berlin Photographic Society, in 1913. He referred in this
report chiefly to the papers written on the subject by Beer and Sachse
in the Photographische Mitteilungen, in 1865, and covered the most
important technical events of the introduction of photography in
Berlin.

Another important work on the subject is the book by Wilhelm
Dost and Dr. Erich Stenger, Die Daguerreotypie in Berlin 1839 bis
i860; einBeitragzur Geschichte der photographischen Kunst (Berlin,

DAGUERREOTYPY IN PRACTICE 285

1922). This richly illustrated work deals with the beginning of pho-
tography in Berlin and its progress up to the general introduction of
photographs on paper. The newspapers printed a great deal about
daguerreotypy. The Vossische 'Leitung published, August 26, 1839,
a full report of the session of the Paris Academy of August 1 9. But the
report was not accepted everywhere in Germany as credible. “The
details of the process had scarcely become known in Berlin, when
immediately some persons arose and designated the whole matter as
a humbug and a Paris swindle” (see Dost and Stenger).

But soon a different view appeared, to which especially L. Sachse,
the well-known art dealer and proprietor of a lithographic establish-
ment, contributed. He had visited Paris in April, 1839, had become
acquainted with Daguerre, and had ordered from Giroux, in Paris,
several pieces of apparatus in order to be the first to introduce them
into Germany (Berlin). It was not until September 6, 1839, that he
received the apparatus, with accessories and printed directions, but,
unfortunately, everything arrived in a broken condition and quite
useless. Thus, he had the disappointment of seeing others precede him
in the first trials with apparatus that they had constructed themselves.
The optician T. Dorffel, of Berlin, anticipated him with a self-con-
structed camera, which he exhibited in his store on the Unter den
Linden, September 16, 1839. Dorffel also made the first daguerreotypes
in Berlin, which he exhibited on the same day. Sachse was unable to
produce his pictures made with French apparatus until a few days later.
On September 30, 1839, Sachse explained the daguerreotype process
to King Friedrich Wilhelm III, at the Charlottenburg Palace, and made
some exposures of the architecture of the place then and there. Like
all other early daguerreotypists, he worked without a reversing mirror,
but his work met with such great approval that he had no difficulty
in disposing of it commercially at a good price (up to 2 Friedrichs
d’or). The daguerreotype apparatus sold by him brought about 400
francs.

Sachse also brought to Berlin the first Petzval lens, October 6, 1841,
with which he made portraits with short exposures. The goldsmith
to the court, Hossauer, also occupied himself with daguerreotypy at
the same time as Sachse. A silver polisher employed by him, Kan-
negiesser, opened a studio at the end of 1 840 and reduced the price of
the popular sizes, so-called J4 and % plates, to respectively 2 and 1 1 / 2
talers, doing a splendid business.

z86

DAGUERREOTYPY IN PRACTICE

Apart from the professional undertaking by Kannegiesser, da-
guerreotypy was pursued only as a side line, usually only on Sundays.
Oehme & Graff exhibited to public view the first showcases with photo-
graphic specimens in Berlin in 1841. By 1852 there were a great num-
ber of photographic studios in Berlin, when the knowledge of the
collodion process introduced a great revolution in photography.

A scholarly research work, written with conscientious thoroughness,
is the illustrated monograph by Wilhelm Weimar Die Daguerreotypie
in Hamburg 1839-1860 (Hamburg, 1915). Weimer enumerates there
the former occupations of the Hamburger daguerreotypists. Thirteen
of them were artist-painters, two lithographers, three mechanics and
opticians, and one each a master painter, art dealer, actor, watchmaker,
chemist, teacher of languages, sea captain, manufacturer of gilt mold-
ings, and a dealer in leeches (E. Stenger, Atelier d. Pbot., 1931,
XXXVIII, 34).

The first report of Daguerre to the Academy of Sciences at Paris,
January 7, 1839, was printed in German newspapers ten days later.

Kobell of Munich asserted that he, with Steinheil, made exposures
and fixed silver chloride images on paper ( Allgemeiner Anzeiger, Na-
tionalzeitung, February 1, 1839; see also a more detailed description
in the issue of April 9, 1839). But this has no more to do with daguerreo-
typy than does the claim of the Reverend Hoffmeister.

ITALY

According to the late Philippo Zamboni, professor of Italian at the
Technical High School at Vienna, who spent his youth at Rome, a
Jesuit father, Della Rovere, studied daguerreotypy very intensively.
He made photographs of several of the papal institutions. He was con-
sidered the best daguerreotypist in Rome; he pursued the art passion-
ately, spared no expense in procuring the best obtainable apparatus,
and delved deeply into the relevant chemical studies. Unfortunately,
as a priest he could not attempt to portray the beauties of Roman
womanhood. Della Rovere stands out as the first photographer who
confined himself to the portraiture of men only.

In addition to the resident daguerreotypists, there were also the
itinerant artists, who traveled from place to place; according to Zam-
boni, in the forties there appeared at the Fair of Sinigallia, such a travel-
ing daguerreotypist, who plied his trade in the market place, as one
finds photographers producing portraits on postcards at the annual
fairs of today (Phot. Korr., 1911, XL VIII, 638).

DAGUERREOTYPY IN PRACTICE

287

SPAIN

In the Wiener allgemeine Theater-Ztg., December 19, 1839, (No.
254, p. 1245) is a report by Adolf Bauerle:

No one could have dreamed of the great sensation which daguerreotypy
created in Barcelona. A short time ago, when this new process was intro-
duced to public use, a sort of festival was celebrated. A huge crowd assem-
bled in the square where the first trial was to be held, and the instrument
was set up, while bands played and flags were flying. The demand for the
first picture made was so great that it had to be disposed of by drawing
tickets in a lottery.

SWEDEN

Dr. Helmer Backstrom has made comprehensive studies on the in-
troduction of photography into Sweden, which he published in Nord
Tidskr. f. Foto. ( 1919, pp. 85, 1 1 3, 155; 1922, p. 1 ) . The first specimen
of daguerreotypy was sent by the Swedish Minister at Paris, Count
Gustav Lowenhielm, and was exhibited, February, 1840, at the Royal
Museum, Stockholm; it was received with great enthusiasm. A Swedish
translation of the original handbook by Daguerre was published in
1839, together with a description of the diorama and Arago’s report
to the French Academy of Sciences. Some months later a small Swedish
textbook on photography was printed in Stockholm, which also con-
tained a description of Talbot’s process. In September, 1840, the
Frenchman Neubourg exhibited and sold daguerreotypes. In July,
1843, the Viennese photographer Weninger made photographic por-
traits in which he used the latest Viennese methods; in the autumn of
the same year the Frenchman “Derville de Paris, eleve de Daguerre”
came to Stockholm and became very famous as a portrait photographer.
The new coin showing the portrait of King Oscar I was modeled after
the picture by him. Lieutenant Benzelstierna made a panoramic da-
guerreotype of Stockholm, which was reproduced by lithography.
He lectured on the subject and gave demonstrations daily, from Jan-
uary to May, 1841. The first public portrait studio was opened in
August, 1841, by J. A. Seven, who, together with J. W. Bergstrom,
was numbered among the best daguerreotypists in Sweden. Daguerreo-
type portraits by amateurs were, of course, made earlier. One such
amateur, Benzelstierna, had the misfortune to cause his sitter, the actor
Georg Dahlzwist, almost to lose his eye, owing to the long exposure
in sunlight, lasting five minutes. In the summer of 1844 Julius Wagner,

288 DAGUERREOTYPY IN PRACTICE

of Berlin, introduced colored daguerreotypes, and he was followed by
Reinhold, of Saxony, and others. Several photographers who later
emigrated from Germany remained in Sweden and became residents.

AMERICA

At the beginning of Chapter XXXII we reported America’s share
in the early development of daguerreotypy. Alfred Rigling, librarian
of the Franklin Institute, Philadelphia, writes in the Journal of the
institute, March 12, 1908, 5 as follows:

In the autumn of 1839, accounts began to appear in the newspapers and
magazines of the United States of the achievements of Louis Jacques Mande
Daguerre, in the field of photography.

One of the earliest notices of the advance in this art was communicated
to the editor of the United States Gazette, by Alexander Dallas Bache, and
reprinted in the Journal of the Franklin Institute for September, 1839. This
was followed in the October number by a brief note extracted from the
Mechanics' Magazine, London, and in November there appeared a trans-
lation by Prof. John F- Frazer, of the original article of Daguerre.

This contained a very full description of the process with illustrations
of the apparatus necessary to carry out the various stages of the operation.

Soon after news reached Philadelphia of the latest developments in the
art of picture-taking Joaquim Bishop, a chemical-instrument maker, then
living at 2 1 3 Cherry Street, and assistant to Dr. Robert Hare, Professor of
Chemistry at the University of Pennsylvania, constructed three cameras
from the description of Daguerre. 6 One of these came into the possession of
Dr. Paul Beck Goddard, an associate of Dr. Hare at the University, another
was turned over to Justus Saxton, a mechanic connected with the United
States Mint, and the third became the property of Robert Cornelius, a sheet
metal worker, who was in business at 176 Chestnut Street.

The report of Alfred Rigling, however, contains a number of gross
misstatements. For instance, he confuses Dr. Paul Beck Goddard, who
was an amateur photographer in Philadelphia and had nothing what-
ever to do with the invention of the bromo-iodized plates, with the real
inventor of this sensitizer, John Frederick Goddard, of London.

It is said that Rigling made the first daguerreotype portrait in
Philadelphia. But this claim is untenable, since the exact date is not
given, while Cornelius’s portrait of himself in November, 1839, is
well documented. Rigling’s undated assertion that the instrument
maker A. Mason was the first to make a photographic copy by arti-
ficial light is also not justified. The priority right for the first daguer-

PETZVAL’S PORTRAIT LENS 289

reotype made under artificial light belongs to the brothers Natterer,
of Vienna, as of March 24, 1841.

The Petzval- Voigtlander lens was introduced in the United States
by Cornelius and Friedrich and Wilhelm Langenheim (1842-43),
Draper and Morse having used a simple meniscus in their practice.
The Langenheims emigrated from Germany and were related to
Friedrich Voigtlander. Together with another German immigrant,
G. F. Schreiber, they opened in the early forties a portrait studio in
Philadelphia (Rohr, Theorie und Geschichte des photographischen
Objektivs, 1899, p. 14); they enlisted as officers and fought in the
Mexican War. The brothers Langenheim made six daguerreotypes of
Niagara Falls in 1846 and sent one each to the heads of European gov-
ernments, for which they received gold medals ( Photographer , 1906,
VI, 265).

Chapter XXXIV. petzval-s portrait lens

AND THE ORTHOSCOPE

At the time of Daguerre’s invention single lenses, such as Chevalier’s
were used exclusively; they were not fast, nor did they give sufficiently
sharp images at full aperture.

Simon Plossl, a Viennese optician, constructed in 1839 a daguerreo-
type camera and also made lenses with improved radii of curvature,
without, however, obtaining an appreciable increase in relative aper-
ture. A great number were sold in place of Chevalier’s lenses, which
were difficult to obtain.

Simon Plossl (1794-1868) was an optician not only of local fame,
but also of wide reputation. He was one of the first to construct achro-
matic microscopes, and subsequently he manufactured good opera
glasses for Petzval.

He entered the optical firm of Friedrich Voigtlander in 1812 as an
apprentice and remained with it for many years. Here he became ac-
quainted with the celebrated botanist Jacquin, for whom he made
certain changes in his microscope and by whom he was introduced
to the astronomer Von Littrow. These two scientists induced him to
establish his own firm in 1823. In 1831 he bought a home of his own,
where, according to custom, his business was also located. It was in this

PETZVAL’S PORTRAIT LENS

290

house that the first lens of the Wollaston-Chevalier type was con-
structed (in the German-speaking countries) . A street in Vienna is
named after him. He competed successfully with the manufacturers
of French and Italian microscopes, who had monopolized the market
until 1829 through Chevalier in Paris and Amici in Modena. Even
Fraunhofer, in Munich, was unable to compete with them, but his
successor, George Merz (1829), made better progress, and Simon
Plossl was crowned with success in 1830, when at a Congress of Ger-
man scientists at Heidelberg he received the prize for the best-con-
structed achromatic microscope. The scientists present at this meeting
spread his name and fame to the four corners of the world. 1

Plossl executed for Littrow new dialytic telescopes in which the
crown- and flint-glass lenses were separated. Plossl seems to have been
the first to perfect the achromatic microscope objectives, and he also
introduced them into England, where afterwards they were made by
Ross (1832), Powell and Lealand (1843), Smith and Beck, though
not for some time, of a quality equal to those of Plossl.

The old optical family of Waldstein played a great role in Vienna.
The firm, which is still in existence, owned its own glass furnaces a
hundred years ago. This “crown- and flint-glass factory” at Ottakring,
a suburb of Vienna, produced such a fine quality of optical glass that,
in the middle of the last century, Waldstein received the gold medal
of the Lower Austrian Trade Society forks excellence. Unfortunately,
the factory was financially unsuccessful and was closed about the year
1858.

A portrait of Simon Plossl, from a lithograph, was modeled by Pro-
fessor Hujer for the “Plossl-Medaille” of the Society of Opticians. 2

The small aperture of Chevalier’s lenses with which Daguerre
equipped his camera was generally deplored. Professor Ettingshausen
recognized at once, when daguerreotypy was first made public, the
insufficiency of the ordinary Chevalier lens, which was exported from
Paris all over the world. As a colleague and friend he was acquainted
with Petzval’s genius for mathematics and optics and induced him to
make a closer study of the problems involved in the construction of
better photographic lenses, to which Petzval responded enthusiastically.

Potonniee writes in his Histoire (1925) that Ettingshausen and Petz-
val calculated the construction of a portrait lens which reduced the
exposure to one-third. This is incorrect, for Ettingshausen himself
never calculated a lens, it was Petzval alone who did so.

PETZVAL’S PORTRAIT LENS

291

Petzval examined the lenses sent from Paris and found himself com-
pelled by the result of his studies to abandon entirely the Chevalier
type of lens and to start new calculations for the construction of large
aperture objectives.

Josef Max Petzval 3 was born January 6, 1807, in Hungary, of Ger-
man parentage. His father was a school teacher. After studying en-
gineering at the University of Budapest, he taught there and became
professor of higher mathematics in 1835. Two years later he was called
to the University of Vienna, in the same faculty, and became a mem-
ber of the Vienna Academy of Sciences. He died September 17, 1891.
Biographical data on Petzval are scarce. He was very secretive about
his personal affairs. In the records of the academy he inserted a dot in
the column for “date of birth.” He lived a secluded life and as a rule re-
jected all attempts to discuss himself or his inventions. Introduced to
him by mutual scientific friends, I succeeded in getting some personal
data formy Ausfiibrliches Handbuch der Photographic (1893, Vol. II,
Part 2) which I have collected above. A halftone reproduction of a
lithographic portrait which Petzval presented to me is printed in the
German edition (p. 385).

As early as 1839 Petzval devoted himself earnestly to the intensive
investigation and profound calculation 4 necessary for the construction
of a large aperture photographic lens, which resulted in his celebrated
portrait lens and a rapid lens for landscapes, later called orthoscope. The
manufacture of these new lenses he entrusted to the optician Peter
Friedrich Voigtlander, of Vienna, giving him designs and the radius
curvatures, without making a contract or guarding his property rights
in the construction and sale. This lack of business foresight he later
regretted, for it caused serious disputes between them. Voigtlander
completed the construction of the first lens in May, 1840, and delivered
it to Petzval. The lens was screwed on to an extremely primitive card-
board camera. It is preserved in the collection of the Museum of Aus-
trian Handicraft, in Vienna (Eder, Phot. Korr., 1896, XXXIII, 470).
Subsequently the whole Petzval- Voigtlander collection was sent to the
Technological Museum in Vienna.

The activity of Petzval extended in 1840 to two types of lenses, one
of which, the portrait lens had a large aperture, about sixteen times as
large as that of Chevalier’s single lenses; the other had a small aperture
(orthoscope) , but a larger and sharper area of definition and was for
use on landscapes and architectural subjects. It was still more rapid than

PETZVAL’S PORTRAIT LENS

2 9 2

the Chevalier lens and was also a doublet. Both types consisted of a
single achromatic landscape lens and another lens, slightly separated
from the front lens, which itself consisted of two separate lens ele-
ments. The designs for the construction and the radii of curvature for
both types are preserved, and the present author recorded them in his
Handbuch (1893, Vol. I, Part 2).

From the mathematical conditions calculated by Petzval there re-
sulted three systems of achromatic lenses, which could be combined
into two types of double lenses. The amount of work involved in
these calculations was considerable and required a number of assistants
in order to expedite the result.

To this end Archduke Ludwig put at his disposal several soldiers of
the Engineering Corps, trained in mathematics, who worked with
Petzval and his assistant Reisinger. The portrait lens was offered to
the public in 1840. A theoretical study of the subject by Petzval was
published under the title: Bericht iiber die Ergebnisse einiger diop-
triscber Untersuchungen (September, 1843).

Petzval’s calculations for the portrait lens and for a second one
(afterwards called the orthoscope) were ready in the early days of
May, 1 840, and Voigtlander’s optical establishment found no difficulty
in their successful manufacture and introduction. Petzval disclosed the
radius of curvatures, the particular kind of glass, the lens distances
only to Voigtlander, his manufacturing optician, keeping them strictly
secret otherwise.

The original figures and working directions for the construction of
Petzval’s first lenses would have been lost to posterity, had not Voigt-
lander disclosed an attested copy of the designs and description, with
the radius of curvature measurements of both systems of lenses, in the
legal proceedings which ensued between them. 5 These were Petzval’s
1841 figures. These documents containing a diagram are published in
Eder’s Handbuch (1893, 1(2), 1 14) and in his work Die photograph-
ischen Objektive (3d ed., 1911).

The glasses used for the first portrait lens were “hard crown and
light flint.” The relative aperture was f/3.6; the first Petzval- Voigt-
lander lenses had only a tube diaphragm, which admitted the full vol-
ume of the light; later came the central diaphragm. The achromatism
was limited, according to Fraunhofer’s system of calculation of the
optic rays; therefore there was a “chemical focus,” to which at that

PETZVAL’S PORTRAIT LENS 293

time little attention was paid, because of the short focal length of the
lenses.

Early in the eighteen-fifties about eight thousand portrait lenses had
been made from Petzval’s design. The specimen Petzval portrait lens
constructed in 1 840 was entrusted shortly afterwards to Anton F. C.
Martin, assistant to Professor Johann Philipp Neumann, of the faculty
for physics at the Polytechnikum, in Vienna, for practical experiments
in photography.

Ettingshausen had discussed the interesting discovery of Daguerre
with Director Prechtl, and the latter had recommended young Martin
for further practical investigation of the daguerreotype process.

It was therefore natural that Petzval should entrust Martin, after
the completion of his first specimen lens by Voigtlander, with the ex-
perimental exposures in May, 1 840. Martin was well equipped to make
portraits on iodized daguerreotype plates and succeeded in doing so
with exposures of 1 J4 minutes by means of the new portrait lens.
These plates excited the greatest interest at the first photographic ex-
hibition at Vienna, in 1864.

The Petzval- Voigtlander portrait lens exhibited in its original form a
much larger aperture than the apertures in the French lenses used by
Daguerre, and this lens was the first which made portrait photography
practical, so that later on, with the aid also of iodo-bromide or iodo-
bromo-chloride plates, portraits could be produced in fifteen to thirty
seconds in a favorable light. Specimen photographs from those times
are preserved in the Technical Museum, at Vienna.

The first lectures on the Petzval lens were given by Professor
Ettingshausen on November 2 and December 8, 1 840, at the Lower
Austrian Trade Association, at Vienna.

THE FAMILY OF VOIGTLANDER 8 — OPTICIANS

The family of Voigtlander, the opticians to whom Petzval entrusted
the manufacture of his lenses, originated in the Harz mountains and
settled in Vienna in the middle of the eighteenth century. The firm
of Voigtlander was founded in 1756 by Johann Christoph Voigtlander
(1732-1797), originally for the manufacture of fine mechanical in-
struments. His successor, Johann Friedrich Voigtlander (1779-1859),
started the optical works in 1815. They were continued by Peter
Friedrich von Voigtlander (1812-1878), who was succeeded by Fried-

PETZVAL’S PORTRAIT LENS

294

rich von Voigtlander (1846-1924). Johann Friedrich Voigtlander
introduced Wollaston’s spectacle lenses first into Germany and later
into Austria. His son Peter Wilhelm Friedrich Voigtlander constructed
the first of the portrait lenses according to Petzval’s calculations. In
addition to the Vienna factory, he erected another at Brunswick in
1849, and he was knighted by Emperor Franz Joseph in 1866. He
directed the factory at Vienna until 1868, when this establishment
was discontinued.. The factory at Brunswick was carried on by his son
Friedrich along the lines of modern developments in the science of
optics.

Friedrich Ritter von Voigtlander advanced the interests of pho-
tography by the foundation in 1868 of the “Voigtlander” medal of
the Vienna Photographic Society, which was conferred in bronze,
silver, and gold for prominent achievements in the field of photog-
raphy. The medal shows his portrait modeled by C. Radnitzky. 7

PRIZE COMPETITION BY THE SOCIETE D’ENCOURAGEMENT IN PARIS FOR

THE IMPROVEMENT OF PHOTOGRAPHIC LENSES; COMPETITION BE-
TWEEN THE VOIGTLANDER AND CHEVALIER LENSES IN I 84 1

The shortcomings of the first Chevalier-Daguerre lens were well
known to Charles Chevalier (1804-1859), as well as to all experts.
The master opticians of Paris, London, Edinburgh, and Philadelphia
labored in vain at the time of the discovery of daguerreotypy to pro-
duce a serviceable and large-aperture lens for portrait photography.
They failed, because improvements could only be made by opticians
who had also command of the higher mathematics.

The optician Chevalier, in Paris, and the mathematician and physi-
cist Petzval, in Vienna, were both experimenting about the year 1 840,
independently of each other, to produce a large-aperture lens, which
led them to the so-called double-lens. Both used an achromatic single
lens (similar to Wollaston’s meniscus), and in addition another pair of
achromatic lenses, some distance apart. These latter consisted of two
lenses separated from each other in Petzval’s lens and two lenses
cemented together in Chevalier’s lens. The basic idea was the same,
but the execution and the final result were different. There followed
in 1841 a prize competition proposed by the Societe d’Encouragement,
of Paris, for the improvement of photographic lenses. Both Voigt-
lander, of Vienna, and Chevalier, of Paris, entered the competition.
Voigtlander sent his Petzval portrait lens with excellent specimen por-

PETZVAL’S PORTRAIT LENS 295

traits. W e have already described this lens, which became known all
over the world.

The Chevalier double-lens was made in two varieties, one for land-
scape and another for portrait photography. For the latter purpose the
front lens was retained in its place, and an additional lens was inserted
behind it in the lens barrel. The “stopping down” was accomplished by
a diaphragm placed in front.

Chevalier had also employed glass prisms with a mercurized hypo-
thenuse to reverse the image in the place of the earlier reversing mirrors.
Chevalier’s double-lens demonstrated as a novel idea the possibility
by changing the rear lens, thus offering a combination of lens positions
which made it suitable for both portraits and landscapes. These lenses
were very faulty, however, from the optical and photographic stand-
point, especially for portrait photography, and did not afford the
clearness and brilliancy of the image in the center of the field given
by Petzval’s lens when sharply focused.

Chevalier was awarded the first prize, a platinum medal, for his
double-lens with variable focal length, in which spherical aberration
was minimized, thus permitting also a variation in the size of the picture
by exchange of the lenses. Voigtlander had to be satisfied with the silver
medal. Historical development subsequently showed that the facts
did not justify the award of this jury, and as early as 1 842 the superi-
ority of the Petzval portrait lens was acknowledged by photographers
everywhere.

Although Chevalier won a higher prize at this contest, he soon
learned from the world-wide success of the Petzval- Voigtlander lens
that his type of lens could not compete with it. All French opticians
imitated the Petzval type, since it was not under patent protection,
and their products were named “Systeme allemand,” but they never
mentioned Voigtlander’s name or that of the inventor, Petzval. The
success of the Petzval lens could not be retarded, and this aroused the
opposition of Chevalier. He seemed to believe at first that the Petzval
lens was an imitation of his production, which caused him to enter a
protest in the same year before the Paris Academy of Sciences. The
subsequent unbiased examination of the optical construction of both
lenses proved conclusively that the types were entirely different and
that Petzval’s lens was an independent and typical invention. More-
over, a scientific controversy arose over the respective merits of the two
types, from which Petzval emerged victorious.

2 96 PETZVAL’S PORTRAIT LENS

Notwithstanding these facts and the unprecedented success of the
Petzval-Voigtlander lens and despite the fact that the history of the
Petzval invention became the common property of the scientific
world, Potonniee, in his Histoire, sets himself up as the defender of
the angry Chevalier and gives an incorrect picture of the history re-
lating to portrait lenses. He writes:

The lens (Petzval-Voigtlander) constructed of four glasses, of great
speed and sufficiently corrected for portraits, enjoyed great popularity,
which was assisted by the fact that it was of foreign origin, because people
prefer those things which come from abroad. They were expensive (450
francs), but the high price also was a factor in their success. Our opticians
protested vigorously that their work was just as good and that the Voigt-
lander lens offered nothing extraordinary other than its price; but their
recriminations were unavailing and nothing was left for them to do but
to name their products “Systeme allemand.”

Eder remarks in a review of this book: “Potonniee does not mention a
single word about the fact that the French opticians simply imitated
the lenses invented by Petzval and constructed by Voigtlander, because
the Austrian patent protection did not extend to France. Contempo-
rary opticians, however, preferred the original to the imitation.” This
loss of business seems to have aroused the ire of Chevalier, who was
otherwise a very distinguished optician, and he wrote in 1844 that
Ettingshausen had seen his lens on a visit to him in Paris. This was the
well-known landscape lens. “Although they did not copy the curvature
of my glass,” says Chevalier, “they exploited my idea, but they ex-
ploited it badly.” Potonniee takes this childish assertion and sets it up as
a fact, claiming that Moigno (1847) and Valicourt (1862) confirm his
position in the matter. “However that may be,” says Potonniee, “one
has seen the prices for the lenses of Chevalier and Voigtlander. Ac-
cording to Lerebours’s catalogue of 1842, a lens ‘Systeme allemand’
cost 200 francs.” Potonniee presents the history of the invention of
photographic lenses solely from the standpoint of the price list of the
French opticians, without the slightest recognition of or scientific com-
ment on the invention of Petzval.

It is in this one-sided manner that this historian describes the revolu-
tionizing of photographic optics by the great exploit of the ingenious
Petzval, who made portrait and instantaneous photography possible for
French as well as for German daguerreotypists, from all of which the
French opticians reaped great profits, owing to their business acumen
and their capacity to imitate and copy.

PETZVAL’S PORTRAIT LENS

2 97

SUCCESS OF THE PETZVAL-VOIGTLANDER PORTRAIT LENS
PETZVAL BREAKS WITH VOIGTLANDER IN I 845

As early as the first half of the forties the commercial success of the
Voigtlander firm with the Petzval lens was extraordinary. The careful
production of the precise functioning Viennese optical works earned
the highest reputation for these lenses; this is demonstrated by the fact
that before the end of the forties many hundreds of these portrait
lenses were shipped from this factory. But Petzval, who had turned
over to the Voigtlander firm his invention without a contract, did not
derive any satisfactory financial return from this success. Personal
differences between Petzval and Voigtlander arose, their relationship
became strained and in 1845 was completely broken off. Petzval re-
fused to have anything more to do with Voigtlander and no longer
used his workshop, but ground and polished the experimental lenses
for his further work in his own shop and with his own hands. He be-
came very efficient and sold several of these “one man” lenses to
private persons, but never sold them publicly. In 1846 he made speci-
fications for a new and specially fast lens intended for a projection
apparatus. In 1 843 he made calculations for the improvement of field
glasses and microscopes. Voigtlander was the first to produce the
Petzval double field glass; its principle is still in use today in opera
glasses and in marine telescopes.

In 1 846 Petzval calculated a new type of photographic lens which
was four times faster than his original portrait lens; it was produced
for several years and then disappeared from the market. Later such
a Petzval lens was found in the possession of the optician Voigtlander
in Brunswick and was submitted to Dr. H. Harting for testing and
recalculation. It consisted of two cemented triplets, from which a lens
was assembled with an aperture of f/2 (Rohr, Theorie und Geschichte
des photographischen Objektivs, 1899). Only then did Voigtlander
acknowledge the correctness of Harting’s supposition that this lens
was a forgotten type, different from the usual construction. Another
Petzval lens of the same type was found in 1870. This lens was useful
only in very small sizes; it was extremely fast and sharp, but it was not
achromatic; its value was largely historical. Another Petzval construc-
tion was a symmetrical lens consisting of two air-spaced doublets, ac-
cording to Voigtlander’s documents, which have only lately become
known. It was constructed in 1872 as a single model and was examined
in 1878 by H. W. Vogel. The lens itself was lost, but the written notes

PETZVAL’S PORTRAIT LENS

298

of Petzval were found among the papers of Voigtlander. The aperture
was f/6.3. Harting found this type practical; it could be made of larger
aperture and might be adapted for the production of motion pictures.
Voigtlander’s stepson, Zinke-Sommer, who worked in the Brunswick
establishment, mentioned that the quadruplet objective of Petzval was
capable of further improvement, but he could not induce Voigtlander
to accept his advice. If the symmetry is not considered, one arrives at
extraordinarily wide aperture lenses as von Rohr demonstrated long
afterwards; The biotar constructed by von Rohr had an aperture of
f/ 1 .6 1 (H. Harting, Phot. Ind., 1924, XXII, 1032).

IMPROVEMENT OF ACHROMATISM
ELIMINATION OF FOCAL DIFFERENCE

At the time of the invention of daguerreotypy the view prevailed
that a lens achromatized to the human eye possessed sufficient achro-
matism for photographic purposes. Therefore the first lenses of Chev-
alier and Petzval were achromatized only according to Fraunhofer’s
specifications. The first to observe that the optical focus of such lenses
was not identical with the focus of the “photochemically active rays”
was Townson, who in 1 840 recorded this in the Phil. Mag. (XV, 381).
Anton Martin also observed during his first tests of the Petzval lens,
in 1 840, the focal difference, to which, however, little attention was
paid by the professional photographers of his time. Claudet, in Paris,
dealt with this exhaustively ( Compt . rend.., May 20, 1 844, XVIII, 954) ,
and so did Cundell. Claudet gave exact information on the various
positions of the “foyer optique” and the “foyer photogenique ou
chimique” and returned to the research of these phenomena in 1849
and 1 85 1 . 8 Claudet’s investigations encouraged the Paris optician Lere-
bours (1807-1873) to construct, in 1840, lenses without focal differ-
ence, and he associated himself later with Secretan, an officer in the
Engineers Corps, for the purpose of the manufacture of such “actini-
cally corrected” lenses (Rohr, Theorie und Geschichte des photo-
graphischen Objektivs, 1899, p. 101).

DIAPHRAGMS

The favorable effect of diaphragms (stops) in lenses on sharpness
and depth was well-known long before the invention of photography.
Niepce knew of this effect as early as 1816. Daguerre-Chevalier, in
1839, used diaphragms fixed at some distance from the lens. When

PETZVAL’S PORTRAIT LENS

2 99

double-lenses were introduced, a blackened metal plate with a round
opening was inserted between the two lenses. On the first Petzval-
Voigtlander double objectives (1840) it was necessary to unscrew
the front lens every time, insert the stop and replace the lens. But it
was not long before the well-known loose or curtain stops were in-
troduced.

Frederick Scott Archer made his wet collodion exposures in 1853
with such diaphragms and then followed Waterhouse’s recommenda-
tion in 1857 (that of a slot for the diaphragm in the lens barrel); in
England they were called Waterhouse stops. In 1859 Voigtlander
fitted all portrait lenses in this manner.

On smaller lenses, that is, wide-angle lenses, so-called rotating or
revolving diaphragms were used, which consisted of a blackened
metal disk which could be turned and had apertures (stops) of various
sizes cut in it.

Ch. Chevalier used rotating stops first for his microscope and in
1841 also for his lenses (see Rohr, Zeitscbr. f. Instrumentenkunde ,
1909, p. 138). The Englishman John Benjamin Dancer also proposed
rotating stops on photographic lenses, in 1856; this is described in the
English patent granted on September 5, 1856 (No. 2064).

The iris diaphragm was used by Niepce in 1 8 1 6 on his camera ob-
scura, this being the first diaphragm of its kind employed in photog-
raphy; it differed very little from those in use today. It is preserved
in the Niepce Museum at Gras, near Chalons.

The iris diaphragm was first made public by Charles Chevalier,
who presented it before the Paris Societe d’Encouragement in 1 840.
Nottone, in 1856 (Phot. Jour., Ill, 165), Jamin (Bull. Soc. franp. d.
phot., 1857, p. 178), and Quinet (ibid., i860, p. 31) recommended
similar iris diaphragms.

Karl Pritschow of the Voigtlander firm discusses at length the his-
tory and theory of iris diaphragms in Phot. Ind. (1926, XXIV, 222).

PETZVAL DESIGNS A LENS FOR LANDSCAPE AND REPRODUCTION PHOTOG-
RAPHY, ALLIES HIMSELF WITH THE OPTICIAN DIETZLER (1854), TAKES

OUT A PATENT FOR “PHOTOGRAPHISCHEN DIALYTEN” (ORTHOSCOPE)

1857, AND ENTRUSTS DIETZLER WITH THE MANUFACTURE OF HIS

LENSES

With the invention of the wet collodion process the demand for
larger sizes developed in the photography of landscapes, architecture,

PETZVAL’S PORTRAIT LENS

300

and for photomechanical reproduction. This demanded larger lenses.
The Imperial Military Geographic Institute of Vienna, as well as the
Government Printing Office in Vienna, called this to Petzval’s attention
in the fifties and directed his studies along these lines.

Petzval recalculated his figures of 1840, which were subsequently
embodied in the “orthoscopc” lens. He revised his figures, ground
and polished in his own shop models according to this formula, and
obtained with them pictures of large size, sharp at the edges, with a
proportionally small aperture and fairly even illumination. In 1854
he secured the assistance of the optician Dietzler, of Vienna.

As early as 1856 he had finished the construction of his “Photo-
graphischer Dialyt” (dialytic photographic lens), and he exhibited
in that year some of the exposures made with these lenses at the meeting
of German physicists and members of the Society for Natural Sciences,
which was held that year at Vienna. He also made a group photograph
of those present at his lecture.

In order to protect the construction of this lens, he applied on
October 6, 1857, through Dietzler, for an Austrian license, which
was granted a few months later. The description of the apparatus in
the application for the license is signed by Joseph Petzval.

This lens was put on the market in 1857 and met all requirements
of the governmental departments mentioned above. It was used for
more than ten years almost exclusively for reproduction purposes, but
it was also by far the best landscape lens of its time, so that many
lenses of this type were sold to professional photographers. Petzval
used this type also in his terrestrial telescope, which he described in
1858 to the Vienna Academy of Sciences. The first of these telescopes
constructed by Dietzler was sent to London by Petzval.

petzval’s first orthoscopic lens

The orthoscope No. 1 of Petzval-Dietzler was presented by the
author of this history to the collection of the Graphische Lehr- und
Versuchsanstalt, in Vienna. It was brought to him in the late nineties
by Dr. Adam Pollitzer, to whom Petzval gave it as a souvenir when
Dr. Pollitzer, in the fifties, refused to send him a bill for curing him
of a disease of the ear.

petzval-dietzler’s portrait lenses

Petzval entrusted to Dietzler also the manufacture of his portrait

PETZVAL’S PORTRAIT LENS

301

lenses and personally supervised the construction of the first hundred.
These undoubtedly are the best type of Petzval lenses in existence. 9

Dietzler and Voigtlander exhibited their competing lenses at the
International Exhibition, in 1862, in London, and both received equally
high awards. Dietzler’s business prospered, sales were good, and his
price lists appeared in rapid succession until 1862. After this Dietzler
failed rapidly.

The business was badly conducted, lenses were sold at cut prices,
the management was unreliable, and the sales diminished. Dietzler
gradually became insolvent, and finally all his stock of lenses was sold
by auction. At this sale lenses which were faulty and untested were
sold, and this further confirmed the bad reputation of the firm. Petzval
had separated from Dietzler in time, and deeply discouraged, refused
any longer to have any connection with lens making.

Voigtlander retained his position in business and applied his energies
in the years following with continued zeal to the making of Petzval-
Voigtlander lenses. At the Paris Exposition of 1867, only Voigtlander
exhibited, Dietzler had disappeared. 10 After having been supported by
contributions from members of the Vienna Photographic Society, he
died in poverty on October 21, 1872.

For his tests with the new “orthoscope” Petzval required a portable
camera with a large plate-holder for landscapes and for reproduction.
He contructed such a camera with his own hands and gave a descrip-
tion of it to the Academy of Sciences, Vienna, in 1857 ( Akademie der
Wissenschaften, Vienna, 1857, XXVI, 66).

A solidly constructed tripod carries on top a triangular bar of wood
4-inch thick, laminated with several pieces to avoid warping, and
heavily varnished. To this bar two cameras, a large and a smaller one
joined together, were fastened.

Petzval was fully alive to the importance of camera construction,
and in his report, mentioned above, made this characteristic statement:
“It is essential that the camera obscura should be made with the
greatest accuracy, because it must be closely adjustable to the peculiar-
ities of the lens if the lens is to function at its highest efficiency.”

CONTROVERSY BETWEEN PETZVAL AND VOIGTLANDER OVER THE
MANUFACTURING RIGHTS TO THE ORTHOSCOPE

As soon as the great success of the Petzval-Dietzler “dialytic lens,”
which later became the “orthoscope,” became known, the Voigtlander

PETZVAL’S PORTRAIT LENS

302

firm in Brunswick took up the manufacture of the new Petzval lens.
Voigtlander recognized in this lens the construction earlier designed
by Petzval for a landscape lens, to which he had paid no attention at
the time. Even Petzval had forgotten that he had turned over to the
Voigtlander firm the design and radii of curvature figures of this lens.
Voigtlander now pushed the manufacture of this type and placed them
on sale under his own name, as the “Voigtlander orthoscope.” This
name (but only this) was invented by Voigtlander, whereas Petzval
intended to call this type “Photographischer Dialyt.” Voigtlander’s
keen competition made itself felt on the Petzval-Dietzler business and
forced Petzval to give his lens also the name “orthoscope.” Voigt-
lander substantiated his rights to the construction by asserting that in
1840 he had already made a model of it and that he therefore had ac-
quired the proprietary rights which the inventor had now given to
Dietzler. Petzval opposed what he called the arbitrary manufacture
by Voigtlander, but the latter insisted on his claim, and the long and
acrimonious dispute disclosed that Petzval in the course of the years
had entirely forgotten that he had actually turned over to Voigtlander,
at Vienna, in 1 840, the first data for the construction of this lens, as
well as those of his portrait lens. Although this controversy disclosed
that Petzval doubtless was the inventor of both types, he derived no
pecuniary returns from them, because he had not protected himself
by making a contract that would assure him of his share in the finan-
cial returns from his inventions; so both Dietzler and Voigtlander
“orthoscopes” were placed on the market for sale.

The American opticians Harrison and Schnitzer, in New York, also
manufactured “orthoscopes” fitted with iris diaphragms in the center,
while in Voigtlander’s orthoscope the diaphragm was inserted behind
the rear lens ( Handbuch , 1893, 1(2), 139).

petzval’s last years

Until 1858 Petzval made an exhaustive study of the science of
dioptrics (refractions of light). His reports to the Vienna Academy
of Sciences in 1857 and 1858 show how earnestly he devoted himself
to the problems of optics, and that he looked forward with confidence
to their solution. But the prolonged disagreement with Voigtlander
and the failure of Dietzler depressed him greatly. He made use of his
masterly knowledge of grinding and polishing lenses and constructed,

PETZVAL’S PORTRAIT LENS

303

without assistance and with his own hands, a newly invented and im-
proved lens. We have the solitary model of that lens, preserved by an
accident from total destruction. A burglary of his summer residence
on the Kahlenberg, near Vienna, in 1859, during which the completed
manuscript dealing with his theory of optics was destroyed, caused
him to turn from optics entirely and to devote himself to acoustics. 11
In 1862 he terminated also the lectures on dioptrics, which he had
delivered since 1853.

He married his housekeeper in 1869; the marriage was happy, but
without issue. His wife died in 1873. On his seventieth birthday he re-
tired from his professorship, greatly respected and decorated by the
emperor. He now withdrew himself from everybody and became more
and more misanthropic and lonesome. He was embittered by his quarrel
with Voigtlander, by the failure of his enterprise with Dietzler, by
the lack of reward for his life’s work in applied optics, and by the ill
will of his colleagues, with whom he was in constant contention; thus
he passed his last years. He received the visits of a few old friends,
but retired more to himself and died of infirmity due to old age on
September 17, 1891.

In his last years the caretakers of the house looked after him and
nursed him, and his will made them his heirs; but, of course, they had
no appreciation of the heritage that had fallen into their hands.

Dr. Ermenyi, of Vienna, arranged Petzval’s carelessly kept papers,
which were partly ruined, giving his report of them in a pamphlet
entitled, Dr. Josef Petzvals Leben und Verdienste (1903). 12

Petzval was a member of the Academy of Sciences in Vienna,
founded in 1 846. He was made an honorary member of many scientific
societies. He was also one of the founders of the Photographic Society
of Vienna. Immediately after his death the society decided to erect
a monument to his memory in the hall of the university, which was
presented to the rector of the university on November 6, 1901, by
the president of the society, at that time the author of this work. 13
A monument at his grave, erected by contributions from a circle of
artists and scientists engaged in photography, was dedicated on October
17, 1905 (Phot. Korr., 1905, XLII, 535, 547; 1907, XLIV, 107, 155).
A street in Vienna was named Petzvalgasse, and finally the Minister
of Education caused a Petzval medal to be stamped, to be awarded to
those contributing meritorious service in the field of photography. 14

304

PETZVAL’S PORTRAIT LENS

APPENDIX

The librarian of the Graphische Lehr- und Versuchsanstalt, in
Vienna, Eduard Kuchinka, reports in the Phot. Korr., (1921, LVIII,
261) as follows, on large Petzval lenses:

In the beginning Voigtlander made only small portrait lenses of the Petz-
val type. In 1851 they were producing lenses four zoll (1 zoll=2.6i cm.)
in diameter. The five-inch Voigtlander came on the market in 1856 (Martin
Neuestes Repertorium der Photographie, 1856) and cost 450 talers. In the
same year we find a six-inch lens offered by Dietzler for twelve hundred
florins.

From a remark printed in the catalogue of the Berlin Photographic
Exhibition of 1865 (p. 39) we note that there existed six-inch lenses in
1856; there is also announced, as exhibited by Leonhard Biilow, of Mos-
cow, “the portrait of a Russian general of the cavalry, taken from
life nine years ago with a large instrument.”

In i860 (Horn, Phot. Jour., i860, XIV, 36) Voigtlander brought
out two types of the six-inch diameter lens with long and short focus,
a good-sized, heavy lens weighing 14.3 kilograms (31 1/5 lbs.) . Others
who made six-inch lenses were Hermagis, in Paris, Busch, in Rathenow,
and others. These models can be found today in such museum collec-
tions as the Graphische Lehr- und Versuchsanstalt, in Vienna.

The optical establishment of Busch, in Rathenow (Prussia) , started
in active competition with Voigtlander (Rohr, Zeitschr. f. lnstrument-
enkunde, XLV, 477) and brought a seven-inch diameter lens on the
market, which Voigtlander answered with the production of an eight-
inch lens in 1864. This is first mentioned in the report of the Vienna
Photographic Society, October 18, 1864 {Phot. Korr., 1864, I, 143).

Ludwig Angerer, who was a member of the executive committee
of the Photographic Society of Vienna at the same time as Anton
Friedrich 15 manager of the Voigtlander branch establishment in Vi-
enna, probably learned from him of this lens, bought it, and worked
with it considerably.

We find two examples of this lens in Voigtlander’s exhibit at the
International Photographic Exposition, Berlin, 1865 (the first in Ger-
many), one of them loaned by Angerer. These two eight-inch lenses
flanked the comprehensive exhibit, the arrangement of which was
photographed and was later awarded the prize medal. There were three
six-inch lenses exhibited, one attached to a camera with two tripods,
owing to the weight of the lens. There is no mention of the eight-inch

PETZVAL’S PORTRAIT LENS

305

lenses in the catalog of the exhibition, probably due to the printing of
the catalog before the lenses arrived. One of the exhibits was a large
photograph taken by Dobbelin & Remele 10 with a thirty-six millimeter
spherical Busch lens.

In the Phot. Korr. (1865, II, 168) we find the following report:

Ludwig Angerer exhibited portraits, busts, and three-quarter lengths,
taken with an eight-inch Voigtlander lens. From the technical standpoint
these were highly successful and vigorous without retouching, but, un-
fortunately, they were not as much appreciated as the difficulty of their
production made them deserve. The pictures measure i 6!4 by 22 inches;
but, of course, this size has neither the freedom of arrangement nor the
sharpness and delicacy of a portrait the size of a visiting card. The nucleus
of his exhibit were the portraits, size 13x16 inches, taken with a six-inch
Voigtlander lens.

H. W. Vogel also mentions the exhibit of the eight-inch lenses in
Phot. Mitt. (1865-66, II, 68). Since the considerable weight of this
lens excluded the use of the customary tripods, Angerer ordered a tri-
pod constructed from his own design, which permitted the raising and
lowering of the camera, as well as its inclination upwards or down-
wards, by the operation of levers. The camera, with lens and tripod,
weighed 200 lbs.

The price of the eight-inch lens was 1,000 talers, according to Mar-
tin’s Handbuch (6th ed., 1865, p. 519); of the six-inch lens only 420
talers. The latter was offered as late as 1884 by a Vienna firm for 1,260
marks.

Hermagis, in Paris, also constructed an eight-inch achromatic double
portrait lens (price list of Oskar Kramer, in Vienna, March, 1865, and
Hermagis’s list, 1867); it was sold for 4,000 francs. There is no proof
that the lens was ever manufactured; while in Kramer’s catalog a
camera is mentioned for Hermagis’s eight-inch lens, but no details are
given of the camera stand, bellows, or of the price.

In 1868, at the third German Photographic Exposition at Hamburg,
photographs by L. Angerer, taken with the six- and eight-inch lenses,
were exhibited.

The finished eight-inch lens, which marked an epoch in the history
of the Voigtlander firm, was given the nice round number of “16,000.”
If we did not know, as mentioned above, the exact date of its produc-
tion, we might yet guess approximately the number of the lenses pro-
duced annually, because at the end of 1861 there had been produced

306 PETZVAL’S portrait lens

in Brunswick the io,oooth lens, which was celebrated on February-
22, 1862, by a special holiday ( Zeitscht . f. Phot., 1862, V, 38). There
were constructed in Vienna and Brunswick 2,000 lenses yearly, and the
probable number 1 6,000 would lead to August, 1 864. And for all these
Voigtlander had paid Petzval in 1840 about 2,000 florins ($1,000).

After Angerer’s death his son-in-law Winter took over the manage-
ment of the well-known establishment and found both the six- and the
eight-inch lenses in the attic. The latter was procured by the author for
the collection of his institute; the eight-inch lens, known in Vienna
technical circles as the “1,000 florins lens,” reached the university
astronomical observatory at Vienna, whose director had long desired
a large lens in his astro-photographic studies. The eight-inch lens No.
16,000 is preserved in the same institution. Such is the history of the
largest lens produced at the Voigtlander works.

This, however, is not the end of the construction of these colossal
lenses. Emil Busch, of Rathenow, continued the race by producing a
ten-inch lens. This lens was an attraction at the International Photo-
graphic Exhibition in Paris in 1867. R. J. Fowler in the Brit. Jour.
(1867, XIV, 366) described it as a “mammoth lens” ten inches in
diameter, which is capable of taking a picture about 30 x 30 inches. The
focus is about 34 inches, and it is asserted that a photograph was made
with it on a collodion plate in 2 minutes.

From the Phot. Mitt. (1867, III, 312) we learn that Karl Suck ex-
hibited a portrait at the February 15, 1867, session of the Photographic
Society at Berlin, which was taken with the colossal lens made by Emil
Busch, of Rathenow, destined for the Paris Exposition. The size of the
picture was 64 x 80 cm. (25 x 31 1 / 2 in.), and portrayed a lady whose
head was 10 cm. (about 4 in.) high, while the size of the entire figure
seated was 54 cm. (21 % in.). The picture was sharp in all parts and
full of detail. Suck exposed under a “rather dark sky for two minutes
and obtained a fully exposed negative; the distance of the sitter from the
lens was fourteen feet.

Busch did not produce more than this solitary example, which was
and remained a showpiece; it was returned to its home, preserved until
1902, and then lost. It seems that is was accidentally damaged and was
then destroyed.

This history would be incomplete without mention of the French
opticians, who, long before the German opticians, produced giant lenses
(from Petzval’s type and radii of curvatures) . Horn’s Phot. Jour. (1855,
IV, 8) reports:

PETZVAL’S PORTRAIT LENS 307

A lens of ten-inch diameter. Very interesting demonstrations were
made quite recently by Disderi at Paris in the presence of a large audi-
ence of scientists, artists, journalists, and amateurs, among whom attend-
ed Messrs. Chevreul, president of the World Exposition jury, Leon Cog-
diet, Dantan, Girod, Count Olympe Aguado, Edouard Delessert, Vicomte
Vigier, etc. The object of the gathering was the demonstration of a lens
with composite glasses, newly constructed by Messrs. Lebrun and Maes,
and of a diameter of not less than 270.7 mm. (10% in.).

Four portraits were obtained during the session with this gigantic ap-
paratus with a diaphragm opening of 10 cm. (4 inches) and from a dis-
tance of three meters (10 feet), Dantan’s portrait, two-thirds life-size,
Count Aguado’s somewhat smaller, and two of Ed. Delessert, life-size.
These four positives on collodionized glass were wonderfully successful.
The exposures varied from two to fifteen seconds. The portraits showed
very little distortion, good lighting, and great detail. While these results
proved that Messrs. Lebrun and Maes had constructed a good instrument,
notwithstanding its extraordinary dimensions, they also gave new proofs
of the well-known skill of M. Disderi. The glass plates with which he
operated were at least 60 cm. wide by 80 cm. high (23^x31 V 2 in.).

Such a lens cost in Paris, with camera and plate holders of polished
walnut, 20,000 francs (Horn, Phot. Jour., IV, 48). The complete lens
consisted of four glasses 27 cm. (10% in.) in diameter (Kreutzer,
Jahresber. d.Phot., 1856, II, 146).

A few months later a short note was printed in La Lumiere (June
30, 1855, p. 103) that W. Thompson and Bingham had taken life-size
portraits on collodion plates, 80 cm. high ( 3 1 VJ in-)> with a twelve-
inch (33 cm.) lens by M. Plagniol and a camera four meters long
(15% ft.) made by A. Gaudin et Freres.

We add a chronology of the genesis of large-size portrait lenses, in
order to make the foregoing easier to follow:

Four-inch lens 1851, Voigtlander

Five-inch lens 1 853, Waibl

Six-inch lens 1854, Waibl

Six-inch lens r 857, Busch

Seven-inch lens 1857, Busch

Eight-inch lens 1864, Voigtlander

Ten-inch lens >855, Lebrun & Maes

Twelve-inch lens 1835, Plagniol

VIENNA IN THE FIELD OF PRECISION OPTICS

Moritz von Rohr gives a detailed account {Phot. Korr., June, 1926,
LXII, 57-67) of Vienna’s place in the development of precision optics

1856, Voigtlander
1856, Dietzler
i860, Voigtlander, Dall-
meyer, Ross

1865, Hermagis
18 66, Busch

308 PETZVAL’S PORTRAIT LENS

before 1 848. 17 It is mentioned that the optical works established by
Fraunhofer in Munich surpassed all similar establishments in Germany
and Austria. Voigtlander senior had learned in England the grinding
and polishing of optical lenses. He constructed double telescopes of the
type made in Holland and opera glasses (1823); he employed an ap-
prentice by the name of G. Simon Plossl, who later went into business
for himself. Von Rohr continues:

There were others in Vienna, who followed with interest the growth
and results of the Munich output, which was astonishing in its enormous
volume, considering the circumstances of the times surrounding industri-
ally inferior Germany. These were the scientists connected with the Poly-
technical Institute founded in 1841, especially those engaged in the field
cf optics, Director J. J. Prechtl (1778-1854) and his subordinate, the sci-
entist S. Stampfer (1792-1864). They maintained the best of relations
with the Bavarian establishment, which they admired, and were on the
friendliest footing with Fraunhofer. Their relations with George Reichen-
bach (1772-1826) were so intimate that he himself installed, in 1819, the
mechanical workshop in their training school at the Polytechnikum. The
workshop was supervised by the able mechanic Starke, who assisted
Fraunhofer in the construction of the Dorpat telescopic lens. 18 Prechtl,
two years after Fraunhofer’s death, was able to report his remarks on the
molding of large sheets of optical glass. The practical workers were given
an opportunity of keeping in touch with new developments by Prechtl’s
Jahrbiichern des Kais. kon. polytechmschen Institutes, in Vienna, which
furnished periodical reunions with those whom he cherished even after
they had left the institution and entered practical pursuits. Prechd’s
Technologische Encyclopddie, published in 1831, demonstrates the com-
prehensive manner in which the technical sciences were taught at this
institution.

During Fraunhofer’s life no attempt was made to enter into competi-
tion with the enterprise which he directed, but this evidently changed
soon after his death, in June, 1826. After Fraunhofer’s successor was ap-
pointed, Prechtl and Stampfer changed their position, because they recog-
nized now the possibility of assisting the Vienna opticians, for whom they
felt they had a mandate of guardianship in scientific progress— of course,
unfortunately, to the detriment of the orphaned Munich establishment.

In order to familiarize the two principal Viennese opticians, Voigt-
lander and Plossl, with the design of Fraunhofer’s lenses, Stampfer pub-
lished in 1828— about eighteen months after the master’s death— two illus-
trated reports on his study of these lenses. The first of these reports dealt
with an accurate method of measurement to determine the radii of cur-
vature of Benediktbeurener 10 lenses, while the second dealt with an

PETZVAL’S PORTRAIT LENS

309

attempt to discover the fundamental thought which had guided this ex-
cellent expert in their construction. Even today Stampfer’s works are still
M'ortli reading, though one may not wholly agree with him.

Since it was intended, of course, to make their proteges in Vienna
capable of properly grinding and polishing lenses, Prechtl published in his
book Praktische Dioptrik (1828), a process for testing, grinding, and
'i''-’ 1 ffcg which, according to E. Voit, 20 was very similar to the meth-
od by Fraunhofer. The exceedingly sensitive Newton’s rings’ test, to
be sure, remained unknown to the Viennese instructor; it seems to have
been carried on secretly in Munich.

It is certain that Prechtl also had to look after the supply of glass which
could be furnished to some extent again, since 1818, by the reopened
glassworks of P. L. Guinand, at Les Brenets. It was advantageous for
Vienna that the Swiss glass manufacturer, as we learn from his statements
in 1814 and 1816, had as his confidential representative the well-known
Vienna optician A. Schwaiger. We may presume that active scientists
like Prechtl and Stampfer would keep themselves informed about these
matters. It is certain that Prechtl, in 1834, was well informed about the
most capable of the small Swiss glassworks, since he discloses an accurate
knowledge of the prices at which Guinand flint- and crown-glass plates
were sold there. This factory was at that time under the management of
a company formed from former individual enterprises by Guinand’s wid-
ow, Rosalie, Th. Daguet, and A. Berthet. We may surely assume that
Prechtl even then either himself advised or caused to have advice given to
his Viennese proteges in the manipulation of the optical glass which they
bought in western Switzerland. This opinion is strengthened by the re-
ports of H. Harting on the different kinds of glass used by W. Fr. Voigt-
lander, which probably relate to this period, because we can find no other
good reason for a combination between the two smelters Daguet and
Berthet. The date is not documented, but we would assign about the year
1 8 34 for this association.

Presumably the giving of counsel to the native opticians fell to S.
Stampfer, whose name appears frequently in the Voigtlander papers re-
ferring to such matters.

It is certain that in 1829 he designed, at the request of A. Rogers, 21 new
distance lenses (dialyte) for celestial telescopes, which, in fact, were soon
executed by Plossl, who in later years sold this now-abandoned type of
telescope on a large scale. The diameter of the aperture is given as up to
27 fi cm. (about io'/h in.). It is probable, although the evidence is debat-
able, that Stampfer also assisted this same master craftsman in the con-
struction of his lenses for microscopes. The requirements for these par-
ticular constructions, as we know, refer back to the respected scientist J.
Fr. v. Jacquin, who, experienced in microscopy, gave to the Vienna op-

3 io PETZVAL’S PORTRAIT LENS

tician the advice of a specialist, which Fraunhofer lacked in this field. It
seems as if the progress made in the combination of several achromatic
lenses by the Paris opticians V. and Ch. Chevalier (father and son) in
1824-25 should also he credited to Plossl, and one may conclude that
Stampfer also collaborated, since, probably after January, 1841, he fur-
nished Voigtlander accurate directions for the radii of curvature and lens
distances for microscopes.

It is certain that young Wilhelm Friedrich Voigtlander owed
nical education to Stampfer, presumably during the early thirties of the
last century and, what is important, also studied under him the processes
of determining the refraction factors of certain prisms under considera-
tion.

Beneficial as the activity of Prechtl and Stampfer was for the establish-
ments conducted by the Vienna opticians, one cannot help but think that
their services were offered almost too liberally. These manufacturers
probably became so accustomed to receiving this gratuitous co-operation
as due to them that they soon suppressed any feeling of appreciation; they
do not anywhere mention Stampfer’s work on the theory of spectacles,
published in 1831, of which they were certainly cognizant.. In another
place I have pointed out that, to my surprise, none of these Vienna firms
deemed it advisable to express in its catalog their appreciation of Stamp-
fer’s mathematical contribution. This erroneous appraisal of the relative
importance of the designing and making of lens units indicated increasing
difficulties in any lasting collaboration of scientists and lens makers. As
the event proved, this was perhaps the principal reason for the decline of
applied optics as an industry in Vienna.

If we have followed Stampfer’s guardianship, it is easily understood
that he chafed under the disadvantages of being obliged to obtain his glass
supply from abroad, and his joy may be imagined when he seemed to
have reached the nationalization of the art of making optical glass through
the efforts of Jacob Waldstein (1810-1876). He, no doubt, did everything
in his power to procure a favorable reception for the first experimental
meltings made in 1840-42. In fact, 1844 saw the opening of the first works
for the production of optical glass in Vienna. We also know from the re-
port of Harting that Stampfer tested melting specimens which were pro-
duced at the Waldstein glassworks. This enterprising business man was
enabled to start these works with the assistance of workmen whom he
had induced to leave Benediktbeurn and who brought with them the
training received there. This loss crippled the older institution, which,
while continuing in existence, no longer played any role in the world
trade.

It must at this time be pointed out briefly that the whole scientific
world was thrown into a turmoil by Arago’s report on January 7, 1839,

PETZVAL’S PORTRAIT LENS

3 1 1

in which he made the first announcement of daguerreotypy. The supply
of photographic lenses— at that time only for landscape subjects— came for
the moment from Paris; but the alertness of the Vienna optician is best
indicated by the fact that at that time Plossl was experimenting with his
own construction of a new type of double lenses.

The problem to be solved, if the prospectively profitable field of pic-
ture making opened by the new invention was to be made accessible, con-
sisted, in modem terms, of the manufacture of a camera lens of high
relative aperture and of medium-sized field. The technical opticians were
therefore faced with an entirely novel problem, and it seems quite im-
possible today that a solution could have been obtained by the amateurish
experiments of the purely rule-of-thumb-trained optical workers of that
time. They naturally attacked the problem in the manner with which we
are familiar in the detailed reports obtained from Paris, London, Edin-
burgh, and New York. The great difficulties in the way of the solution of
this problem seem to have become popularly known in the late summer
of 1839, when the details of the process were made public at the
Academy in Paris. It can be pointed out that the first experiments were
unsuccessful, although very efficient and ingenious technical experts
(Prechtl and Stampfer) occupied themselves with the problem.

Among those familiar with this difficult problem was the Viennese
physicist A. v. Ettingshausen, at that time on a visit to Paris, charged by
his government with the duty of attending the delivery of Arago’s report,
who after his return to Vienna brought the subject to the attention of
the young professor of mathematics Joseph Petzval (1807-1891). Al-
though we have no details today of the relationship between Stampfer
and Petzval, it may be set down with certainty that Petzval was acquaint-
ed in a general way with this problem, which scientists worthy of repute
had passed on to the Viennese master opticians, and that undoubtedly the
unique photographs of Fraunhofer and his tremendous performance had
both attracted and stimulated him. His colleague advised him to procure
the necessary information— the indices of refraction and dispersion for
crown- and flint-glass— from the young optician W. Fr. Voigtlander.
Thus began between these two men a chance relationship for which
neither was fitted and which could not result in a successful collabora-
tion. Aided by this information pertaining to the species of optical glass
used, Petzval advanced his work in the analytical development of the cor-
rection of errors in general so diligently that as early as 1840 he had cal-
culated three lenses, after which, following his figures, two double com-
binations with new and desirable properties could be produced.

Petzval could not arrive at a satisfactory conclusion without more de-
tailed information of the results which had been obtained with the lenses
in use up to that period, and the assistance of the amateur photographer

PETZVAL’S PORTRAIT LENS

312

A. Martin (1812-1882) was necessary before the great advance made by
Petzval could be fully appreciated. Naturally, Voigtlander immediately
put the new lens combination constructed in his works on the market. It
is to be regretted that Petzval declined, it seems, the opportunity then of-
fered of a business alliance with the respected and competent businessman
and optician. Apparently unable to appreciate the financial value of the
Prechtl-Stampfer achievement, he may have made a present of his inven-
tion to his optician.

Its commercial success was immediate and extraordinary; and because
the portrait photographers, like eagles watching for their prey, kept their
eyes wide open for rapid lenses, the fame of this new lens, Petzval’s por-
trait lens, spread with unexpected rapidity. Neither W. Fr. Voigtlander
nor his father, experienced in business affairs, took any steps for the me-
thodical exploitation of the prize which had fallen into their laps, more
surprising than a lottery prize; even the safeguards necessary for the pro-
tection of the property rights in Austria and abroad were neglected. Al-
though the opticians of western Europe showed their appreciation of this
new lens series by way of imitation, which imposed on them no further
return, there was still enough left in the brisk demand for the original
product to satisfy the most exorbitant claims.

It is clear that in these circumstances, where at least there was no lack
of approval, Petzval required no urging to continue in the direction in
which he so fortunately advanced. He calculated now another lens com-
bination, still more rapid, as well as the lenses for an efficient telescope,
by the Holland method, and a special lens for projection apparatus by
transmitted light, and turned them over to his business associates. Still he
seems to have felt a disposition to be discontented as the economic value
of the portrait lens became known, so that when Petzval realized more
clearly the commercial value of his “gift” to his optician friends, he nat-
urally regretted his lack of foresight. Unfortunately, Voigtlander did not
make use of this change of mind in his worthy collaborator by binding
Petzval to his enterprise with a fixed contract, but thought that he could
adequately remunerate him for his work up to that time with the sum of
2,000 florins (f 1,000). We cannot go far wrong, if we explain this action
of a businessman who, as is positively proved by later reports, thought
very highly of Petzval’s work as optician, by the pampering attitude to-
wards the Viennese opticians adopted generally by the old directors of
the Polytechnic Institute. It will be recalled that Stampfer’s working out
the results of separation (dialyte) met with no better appreciation from
the Plossl works, although scientific circles recognized in his work a very
remarkable performance. The young head of the Voigtlander firm prob-
ably never considered the necessity of taking a different position towards
Petzval. How far his prejudiced conceit in his own performance extended,

DAGUERREOTYPY AS A PROFESSION

is best shown by his request that his own determination of the indices of
dispersion and refraction be included in the scientific report which Petz-
val published in 1 843 on the elements of his calculation. The denial of his
request seems to have hurt him more than his personal disputes with the
sharp-tongued professor.

The historian of today cannot sufficiently regret this separation after
so short a time, hardly two years of extraordinary success, of two notable
men whose joint efforts ought to have continued. We are led to believe
that Petzval would have been able to accomplish important results had he
remained in closer touch with the requirements of an optical workshop. 22
He would thus have realized and improved the defects in the design of
his landscape lens (orthoscope), as well as the qualities needed to fulfill
his desire to produce faster lenses. Examples of these later productions are
at hand and present a great contrast with the perfect design of his portrait
lens. When we consider the fervent spirit with which he, in the middle
fifties, solved the achromatism of his portrait lens, and if we attribute to
him also the double lens which became known as “cemented dialyte,”
which at least is probable, we cannot help but deplore the misfortune
which cut short so suddenly the progress of scientific optics in Vienna.

And so it happened, that a clever merchant and conscientious craftsman
could enjoy for many years great reputation as producer of perfect
photographic lenses, although he contributed hardly anything to the fur-
ther development of these instruments.

After 1 848 the optical trade in Vienna became smaller and smaller. The
removal of Voigtlander’s activities to Brunswick and the closing of the
factory which was so excellent in its production robbed Vienna of its
leadership in the optical industry. The activities of the English amateur
photographic societies, following Petzval’s second period of photographic
activity in the development of a serviceable wide-angle lens, were not
participated in by any Viennese optician. When at this time K. A. Stein-
heil began his memorable career, Vienna had lost its claim to scientific
superiority in this field.

Chapter XXXV. daguerreotypy as a pro-
fession, 1840-60

The more the application of daguerreotypy was perfected chemically
and optically, the more amateurs, artists, and scientists studied photog-
raphy for their respective purposes. Everywhere it became the subject
of endless experiments. More especially, professional photography as

DAGUERREOTYPY AS A PROFESSION

a business enterprise grew with extraordinary rapidity. In the forties
they were satisfied to take portraits in the open air, in an open corridor,
or on a balcony, and no one paid any attention to the surroundings. The
iron railing of a balcony shown in daguerreotypes of 1844 demonstrates
the absence of elaborate settings. One of 1 848 shows a daring forward
step by including a restless child in the picture. Later studies added
curtains and draperies.

French daguerreotypists achieved wide reputation, especially da-
guerreotypists Lerebours and Secretan, opticians to the observatory
and to the navy in Paris. Before the end of 1839 N. P. Lerebours had
constructed large daguerreotype cameras which produced pictures
of 12 x 15 (French) inches. He worked at first with Gaudin, 1 then
established himself in Paris as manufacturer of optical, physical, and
mathematical instruments at Place du Pont-Neuf 1 3, 2 and later asso-
ciated himself with Secretan. 3 They conducted a photographic studio
at the Rue de l’Est 2 3, in addition to their shop, where they sold optical
apparatus and accessories for daguerreotypes. Their studio was opened
about 1845, and it flourished for several years. In 1850 Lerebours and
Secretan made one of the most excellent panoramic daguerreotypes of
a view of Paris ever made. This was preserved in the technological col-
lection of the Polytechnic Institute in Vienna and was later placed on
exhibition in the Technical Museum there.

In England one of the first professional daguerreotypists was A.
Claudet, who had purchased from Daguerre a license for England
immediately after the publication of the process and had moved from
France to England. He was a practical photographer in London and
experimented with photochemistry and optics. The English photog-
rapher J. E. Mayall also had a good reputation, and his daguerreotypes
of 1850 achieved recognition at the London Exhibition of 1862, where
they were exhibited. In addition to the few daguerreotypists here
named, there were many others too numerous to mention. £ Dr. Eder
reproduced for the fourth edition, 1932, of his Geschichte a few inter-
esting examples, because they demonstrated in connection with the
other daguerreotypes illustrated there the status of photographic pro-
duction in the middle of the last century. 4 ]

The first attempts to portray the human body by daguerreotype as
an aid in the fine arts or for attractive subjects for sale were made in
the forties of the last century in Paris. The earliest daguerreotypes of
this class which I have seen date from 1844-1849 and represent the

COLORED DAGUERREOTYPES

most technically perfect daguerreotypes which have been preserved
from that time. They bear only the name and age of the model and
were undoubtedly made for erotic purposes, for the collection com-
prises, among others, pictures of two persons which could not be re-
produced. 5 It is difficult to determine who took the first group pic-
tures by daguerreotype, since the idea of making portraits of one per-
son and the natural progress to group photography followed each other
too closely. In the Photographic Journal (1905, p. 218) we find the
reproduction of a group picture said to be “the first one taken by Da-
guerre, March, 1843.” It was probably photographed with a Petzval
lens. It was no particular feat to produce pictures of groups with this
instrument; the German and Austrian dagucrrcotypists achieved
equally good results in this field.

Chapter XXXVI. colored daguerreo-
types

The coloring of daguerreotypes seems to have been known as early
as 1840 and the knowledge had spread by 1841. Lerebours, in Paris,
seems to have occupied himself greatly with it. 1

One of the first who colored daguerreotypes was the painter Isen-
ring, of St. Gallen, Switzerland, who exhibited daguerreotypes in one
and more colors on a trip to Augsburg in November, 1 840. He was
one of the first of his countrymen who took up daguerreotypy as a
profession and one of the first to retouch daguerreotypes, by trying to
improve unsharp portraits by laying bare or scratching out the silver
in the eyes. In July, 1841, he opened a daguerreotype studio in Munich;
at that time the production of colored daguerreotypes was no longer
unusual. He did not disclose his process, but it undoubtedly consisted
in the application of powdered pigments, as A. Martin records. 2

In December, 1842, Beard published a method for the technical
simplification of coloring daguerreotypes “by the application of stencil
and powder colors.” 3 Etienne Lechs took out a license in December,
1842, in France (No. 8925) for a “daguerreotype water color process
by means of powders.”

At this time daguerreotype portraits of ladies were not uncommon
in which the gold ornaments and perhaps the delicate fresh coloring
of the cheeks were suggested by the aid of dry colors.

3 i 6 NEGATIVES AND POSITIVES ON PAPER

About 1850 stereoscopic daguerreotypes were colored in Paris.
The coloring was done by dusting-on exceedingly fine powdered pig-
ments.

The Reverend Levi Hill (d. February 17, 1865) sold in America
licenses for the use of a process, invented by him, of daguerreotypy
in natural colors, the Hillotype, which turned out to be nothing but
painting over the daguerreotype.

Colored daguerreotypes did not meet with general approval, since
the coloring was not always done with discretion. Protests were heard
that the coloring of daguerreotypes was not an improvement; it did
not give a painting of the subject and was not a daguerreotype.

For additional information see Eder and Kuchinka, Die Daguer-
reotypie und die Anf tinge der Negativphotograpbie auf Papier und
Glas, Vol. II (3) of the Hand buck, 1927.

Chapter XXXVII. invention of photog-
raphy WITH NEGATIVES AND POSITIVES ON
PAPER AND ITS PRACTICAL DEVELOPMENT BY
TALBOT

Daguerreotypy suffered from a fundamental disadvantage. It could
furnish in the camera only a single photographic image, which was
not capable of multiplication by simple photographic printing methods.
It was not until the invention of so-called photographic negatives, at
first produced on paper which had been made sensitive to light, from
which in turn any number of positives or prints could be made, that
photography took its place among the graphic arts and crafts as a
method of reproduction.

FOX TALBOT

The honor of being the first to introduce a practical and workable
method of photography which gave, in the camera, a negative image
on light-sensitive paper from which positive images or prints could
be obtained by contact printing— as in today’s practice— belongs to
the Englishman William Henry Fox Talbot, a country gentleman of
means who was devoted to scientific pursuits.

NEGATIVES AND POSITIVES ON PAPER

Fox Talbot was born in February, 1 800, the son of William Daven-
port Talbot. He was educated at Harrow and Trinity College, Cam-
bridge, where he devoted himself in particular to the study of mathe-
matics and physics. 1 Talbot lived on his family estate, Lacock Abbey
near Chippenham (Wiltshire) in England, 2 was a member of Parlia-
ment 1832 to 1834 and a Fellow of the Royal Society in London
from 1831. He died September 17, 1877.

Fox Talbot used the camera obscura on a trip to Italy in 1823 and
1 824 as an aid in sketching by tracing the light pictures of the camera
with pencil, on transparent paper, but he was not satisfied with results
thus obtained. During another visit to Lake Como, in October, 1833,
he again attempted to make sketches with the aid of a Wollaston camera
lucida, but this method also presented difficulties and he failed to
obtain satisfactory results.

Without knowledge of the analogous endeavors of Niepce and
Daguerre, the idea ripened in Talbot’s mind that it might be possible
to fix the images obtained in the camera obscura by chemical means.
Being well versed in chemistry and possibly acquainted with the earlier
work of Schulze, Scheele, and Wedgwood with light-sensitive silver
salts, he commenced experiments on the subject after his return to
England in January, 1 8 34. He investigated, first, the action of light on
paper coated with nitrate of silver, and then with chloride of silver.

This description of his first experiments Talbot himself reports in
the Preface of his work, now exceedingly rare: The Pencil of Nature
(London, 1844). The illustrations for this work Talbot made with
his calotype process, printing from the negatives so obtained on silver
chloride paper.

The best copy of Talbot’s Pencil of Nature, according to Charles R.
Gibson, is in the possession of Glasgow University; the prints in the
British Museum copy are much faded, several of them show hardly
a trace of the image. A few years later, Talbot published a second
collection of prints, entitled Sun Pictures in Scotland. A copy of this
book, produced by Talbot, in 1 845, is in the library of the Patent Office,
London. One of the pictures is quite faded out, but the others are
excellently well preserved. The variations in the state of preservation
of the pictures may be traced to the differences in the fixation, and
doubtless atmospheric conditions were in part responsible.

A survey of the historical development of photography presented
by G. H. Rodman in The Photographic Journal (1921, p. 435, and

3 i 8 NEGATIVES AND POSITIVES ON PAPER

1924, p. 523) discusses in full Talbot’s life and work, with illustrations
of the instruments used by him at Lacock Abbey.

Quite unexpectedly, in 1930, a rather large collection of the first
photographs by Talbot was discovered among the effects of the late
Prince Metternich. This Austrian chancellor, while ambassador in Paris
and later, took a great interest in daguerreotypy. He requested Talbot
to send him the report of any new developments pertaining to the
invention of photography and entered into correspondence with him.
Talbot sent to Metternich in 1839-1840 a number of light tracings of
ferns, stained glass, etc., on silver chloride paper, which were fixed.
There were also some photographs of ceramics, which were probably
produced in the camera after exceedingly long exposures. Then fol-
lowed some silver chloride prints from negative images made in the
camera by the process, invented by Talbot, of developing with silver
iodide and gallic acid; the subjects were a portrait and several build-
ings, the prints being still in fairly good condition. These light images
made by Talbot are in chronological order until 1841, but the earliest
calotypes are dated after the granting of Talbot’s English patent. This
collection remained for some years unknown in Metternich’s library
until a portion of it was sold by his heirs. Together with some books
the Talbot prints were bought by Count Hugo Cord, of V ienna, whose
son, the historian Count Egon Corti, recognized their historic value.
He showed them to the author of this history in August, 1930. The
genuineness of these incunabula is indisputably attested by Talbot’s
autograph.

Talbot relates in his Pencil of Nature that he became acquainted in
1837 with the experiments of Wedgwood and Davy datingfrom 1802.
He states:

The reports of Wedgwood and Davy are undoubtedly original and inter-
esting, and certainly give these gentlemen a certain claim to be considered
as the inventors of photography, although the effectively specific progress
is inconsiderable. They actually succeeded in obtaining chemical reactions
of sunlight, but only from featured objects, placed on a piece of paper
suitably prepared . . . they also made experiments to accomplish the prin-
cipal purpose of the art, i.e. to produce images of distant objects with the
aid of a camera obscura, which, however, they failed to accomplish, not-
withstanding very long exposures. We must, therefore, recognize Wedg-
wood and Davy, as the first to initiate experiments which later led to the
success of Talbot and others, but they have no claim to the discovery or

NEGATIVES AND POSITIVES ON PAPER

319

invention of a practical process for the production of photographic
images in the camera.

It is quite evident that the way leads from Schulze to Scheele, from
Wedgwood and Davy directly to Talbot, which Talbot himself de-
clares and other English scholars, such as Charles R. Gibson, confirm.

In his first experiments Talbot coated the paper with the moist
precipitate of silver chloride. Then he discovered a better way; he
saturated the paper first with a strong solution of common salt, dried
it, and then immersed it in a solution of silver nitrate. Adapted as this
silver chloride paper was for contact printing in a printing frame, it
was not sensitive enough for exposures from nature in the camera
obscura, even after hours of exposure.

He succeeded, in 1835, in making his silver chloride paper more
sensitive by repeated baths in a solution of common salt and nitrate of
silver, and in that year he produced a picture of his residence at Lacock
Abbey in the camera obscura on a bright sunny day. The size of the
picture was very small and it has not been preserved or published by
Talbot.

Talbot then used silver chloride paper to copy drawings, engrav-
ings, and manuscripts, and he was the first to apply the method to
what was later called the process of making tracings by light, reported
to the Royal Society in London, January 31, 1839. He also mentions
there that leaves and flowers may be easily reproduced in this manner
in sunlight. He states precisely that silver chloride with an excess of
silver nitrate is more light-sensitive than with an excess of sodium
chloride (common salt) . His early use of a solution of common salt for
fixing his prints gave imperfect results, of doubtful permanency; but
when he learned of Herschel’s “hypo” fixing salt, he adopted it, thus
improving their appearance and ensuring their permanency. In 1834
Talbot’s attention was called to the report of Sir H. Davy of twenty
years earlier, stating that he had found that silver iodide was more
sensitive to light than chloride of silver. Talbot’s experience in his ex-
periments, however, much to his surprise, was just the opposite. The
silver iodide paper became less dark in light than the paper coated with
silver chloride. He observed that even an excess of potassium iodide
annuls the light-sensitivity of the silver salt, and he consequently con-
cluded to fix photographic silver chloride images with a solution of
potassium iodide, a fixative which he found as satisfactory as common
salt.

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320

During this whole period photographic experiments were merely
a side issue with Talbot, who was then particularly interested in
mathematical and physical investigations, especially in the study of
optical phenomena in certain crystals and the phenomenon of light
interference.

When on January 6, 1839, a preliminary general account of Da-
guerre’s invention was published in the journals, Talbot, without any
knowledge of the details of Daguerre’s process, which were not pub-
lished until August, made public his work in the photographic field
and wrote a letter to the Royal Society in London, January 30, 1839,
in which he described his method of production for light images on
silver chloride paper and that of an approximate fixation with an
excess of a strong solution of common salt.

This report was published under the title, Some Account of the Art
of Photogenic Drawing; or, The Process by Which Natural Objects
May Be Made to Delineate Themselves without the Aid of the Artist's
Pencil (London, 1839).

On February 20, 1839, Talbot wrote to Biot, member of the French
Academy, that he fixed his silver chloride images with a solution of
iodide of potassium or a strong solution of common salt, or an entirely
different, effective preparation given him by Herschel, which was to
be kept secret for the present. It was the “hypo.” On March 1, 1839,
Talbot disclosed the fact 3 that potassium ferrocyanide is a fixative, 4
although an uncertain one. At the same time he revealed that the above-
mentioned excellent fixative, given him by Herschel, was sodium thio-
sulphate (hypo).

On March 15, 1839, he wrote a letter to Biot, which was read before
the French Academy, in which is contained the statement that he had
discovered the great light-sensitivity of silver bromide paper ( Compt .
rend., 1839, VIII, 409). He saturated paper with silver nitrate, then
with a solution of potassium bromide, and then once more with nitrate
of silver. He found this paper very sensitive in weak light, and with
it he succeeded in making, in his camera, the picture of a window after
an exposure of six to seven minutes.

Talbot therefore laid the foundation for our photographic printing
methods with bromide and chloride of silver, and Herschel completely
solved the question of perfect fixation with sodium thio-sulphate
(hypo). (On the investigations of Herschel, Becquerel, and others on
the action of the solar spectrum on these photographic papers, see

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3*i

Chapter XXXI). All these inventions of Talbot’s dealt, however, only
with the method of making pictures direct in the camera, and this
could not compete in light-sensitivity with the daguerreotype.

Talbot also discovered later, as mentioned below, the light-sensi-
tivity of bichromated glue; also heliographic steel etching, as well as
copper etching on light-sensitive bichromated glue coatings. He was
an extraordinary, prolific, many-sided, active scientific discoverer and
inventor of photographic processes, which were of far-reaching im-
portance in the practice of photography.

Talbot took out patents on all his inventions and insisted on his
rights as inventor; he prosecuted all who used his processes without
his permission. These severe measures were not helpful to the advance-
ment of photography. Lord Rosse, then president of the Royal Society,
and Sir Charles Eastlake, the president of the Royal Academy, inter-
vened in 1852 and tried to induce Talbot to take a less severely
obstructive attitude in the interest of the arts and sciences. Talbot con-
sented, publicly renounced his patent rights and presented them gra-
tuitously to the public, with the single exception of the commercial
use of his invention; he thus separated the exploitation of his inventions
in trade from their application in the arts and sciences, which enabled
anyone to work with Talbot’s patented processes without being liable
to suit for patent infringement (Phot. News., October, 1877; Colson,
Memoir es, p. 82).

DISCOVERY OF THE DEVELOPMENT OF THE LATENT IMAGE ON SILVER

IODIDE WITH GALLIC ACID BY TALBOT (1840)— PAPER NEGATIVES

(calotypy)

The obtaining of the latent image on silver iodide paper and with
it the method of developing photographs were discovered by Talbot
on September 20 and 21,1 840. In an appendix to Tissandier’s A His-
tory and Handbook of Photography (London, 1878) Talbot states:

This discovery immediately changed my whole system of work in pho-
tography. The acceleration obtained was so great, amounting to fully one
hundred times, that, whereas formerly it took me an hour to take a pretty
large camera view of a building, the same now only took about half a
minute; so that instead of having to watch the camera for a long period
and guard against gusts of wind and other accidents, I had now to watch
for barely a minute or so £ Brit . Journ, Sept. 15, 1905, p. 727; Phot. W o-
chenblatt, 1905, XL VI, 432].

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3 “

During his numerous experiments Talbot turned back (in connec-
tion with daguerreotypy) again to silver iodide, introduced by Da-
guerre into photographic practice, but in all Talbot’s work he held to
the practical importance of his discovery: that a slightly or not visible
( latent ) silver iodide image can be developed and intensified by gallic
acid. Talbot arrived at this method to some extent by accident. In
order to test the degree of their sensitivity, he exposed several pieces
of coated paper, treated in various ways, in the camera for only a short
time, and one of these, which showed no trace of an image, he laid aside.
When he took up this specimen again, he saw to his surprise that a per-
fectly finished negative design had appeared. Fortunately, he remem-
bered perfectly the treatment given to this particular piece of paper,
and thus was enabled to follow up his discovery by retracing the
antecedent steps. He named the process “calotype” (after the Greek
word “kalos,” meaning “beautiful”) on account of the surprising
beauty of the results . 5

The word “calotype” was first used by Talbot in a letter to the
Literary Gazette of February 19, 1841. The particular passage, accord-
ing to Charles R. Gibson in Photography as a Scientific Implement,
is as follows:

I may as well begin by relating to you the way in which I discovered
the process itself. One day, last September, I had been trying pieces of
sensitive paper, prepared in different ways, in the camera obscura, allow-
ing them to remain there only a very short time, with a view of finding out
which was the most sensitive. One of these papers was taken out and ex-
amined by candlelight. There was little or nothing to be seen upon it, and
I left it lying on a table in a dark room. Returning some time after I took
up the paper, and was very much surprised to see upon it a distinct pic-
ture. I was certain that there was nothing of the kind when I had looked
at it before, and, therefore (magic apart), the only conclusion that could
be drawn was that the picture had unexpectedly developed itself by a
spontaneous action. Fortunately I remembered the particular way in
which this paper had been prepared and was therefore enabled immedi-
ately to repeat the experiment. The paper, as before, when taken out of
the camera, presented hardly anything visible; but this time, instead of
leaving it, I continued to observe it by candlelight, and had soon the
satisfaction of seeing a picture begin to appear, and all the details of it
come out one after another.

In this experiment, the paper was used in a moist state, but since it is
much more convenient to use dry paper if possible, I tried it shortly
afterwards in a dry state, and the result was still more extraordinary. The

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3 2 3

dry paper appeared to be much less sensitive than the moist, for when
taken out of the camera after a short time, say a minute or two, the sheet
of paper was absolutely blank.

But nevertheless, I found that the picture existed there, although in-
visible; and by a chemical process analogous to the foregoing, it was made
to appear in all its perfection. ... I know few things in the range of sci-
ence more surprising than the gradual appearance of the picture on the
blank sheet, especially the first time the experiment is witnessed.

Fox Talbot applied for an English patent on his “Calotype Process,” 0
on February 8, 1841 (No. 8842). Talbot treated the paper with nitrate
of silver and then with potassium iodide, which forms a less sensitive
silver iodide. Just before using, he coated it with a compound solution
of acetic acid with silver nitrate and added gallic acid (gallo silver
nitrate), which made it more sensitive to light. After the paper was
rinsed in water and dried, he exposed it in the camera (with lens dia-
phragm f/30, for nine to ten minutes) which, during the relatively
short exposure resulted in no, or almost no, visible image; this appeared
only after an additional brushing over with gallo silver nitrate solution.

At first Talbot employed potassum bromide solution as a fixative,
later (June 1, 1843) a hot solution of hypo; he took out an English
patent on this, as well as on making paper negatives transparent with
wax 7 and on increasing the sensitivity of calotype papers by placing
a warm iron plate under them (June 1, 1843, No. 9753).

Having obtained a negative image, i . e., an image in which the white
portions of the subject photographed were reproduced in black, he pro-
ceeded to make from it positive prints on silver chloride paper. By this
invention Talbot brought photography on paper to such a stage of
perfection that the art was in a position to compete with daguerreotypy.
This process was considerably improved later, in the hands of many
skilled operators ( Handbuch , 1927, Vol. II, Part 3).

The indisputable priority of the invention of a photographic process
for obtaining transparent negative images direct in the camera which
could be multiplied (as positives) in any desired quantity by printing
on silver chloride paper, must be accorded within this description to
Fox Talbot. It is he, who is the creator of the modem “negative pho-
tography.”

A selection of the paper negatives obtained by his calotype process
were used in the illustration of his work The Pencil of Nature ( 1 844),
with silver chloride prints. One of the illustrations is a view of a Paris
Boulevard. A yellowed original is preserved in the Graphische Lehr-

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3 2 4

und Versuchsanstalt, Vienna. This photograph, notwithstanding its
several imperfections, is one of the earliest examples of photography
with paper negatives and one of the rare incunabula of photography.

Talbot also published the first book in which the text is illustrated
with photographic paper pictures. It is entitled: Sun Pictures in Scot-
land (1845). “The plates of the present work are impressed by the
agency of light alone, without any aid whatever from the artist’s
pencil.” It was the first book illustrated with photographs.

The first application of the calotype process to the production of
enlargements Talbot mentioned in his patent specifications, June 1,
1843. He stated that it is possible, by the use of lenses, to obtain from
a small calotype positive an enlarged paper negative, which is printed
from in the usual manner. This was the beginning of the modem
enlarging process.

In 1842 Talbot received the Rumford medal of the Royal Society
in London for his inventions (Phot. Journ., 1855, p. 84).

Talbotypy met with an enthusiastic reception in both professional
and amateur circles. Queen Victoria and the Prince Consort practiced
the art of Talbotypy and ordered (according to Gibson) a photo-
graphic darkroom constructed in Windsor Castle.

Miss M. Talbot, the great-granddaughter of Fox Talbot, presented
to the Museum of the Royal Photographic Society, in London in 1921,
a great number of cameras and accessories which Talbot had used—
for instance, a solar microscope, seven calotype cameras of different
sizes, a large daguerreotype camera with a single lens made by Alph.
Giroux & Co., Paris, another similar camera with a lens by Lerebours,
Paris, one of the first tripods by Charles Chevalier, Paris, iodizing and
developing boxes, specimens of Talbot’s etching process, daguerreo-
types, and a manuscript by Talbot. Of special interest is a camera in
which, through an opening in the front panel, the object could be ob-
served up to the time of the exposure, when the opening was closed by
a cork (Brit. Jour. Phot., 1921, p. 565).

Rodman took a photograph of the vault at Lacock Abbey, which
Talbot used as a darkroom (see “Exhibition Catalogue,” of the Phot.
Jour., 1922, p. 48).

For the use of photography on porcelain Fox Talbot and Malone
were granted a patent in 1849 (Brit. Jour. Phot., 1865, p. 326).

Fox Talbot occupied himself in his last years with unsuccessful ex-
periments to obtain photographs in natural colors. He died September

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3*5

17, 1877 (77 years old ) 8 on his estate at Lacock Abbey, Wilts (Eng-
land), where a monument was erected to his memory (Phot. Korr.,
1921, p. 236).

J . B . READE

The accelerating influence of tannin on the blackening process of
silver paper, seems to have been discovered by an English clergyman,
the Reverend J. B. Reade, in 1839. His work was extremely deficient,
however, in that he saturated writing paper first with a decoction of
nutgalls, coated it with silver nitrate, and then used the moist paper
at once to photograph nature or historical objects in the solar camera.
He exhibited pictures thus obtained at the Royal Society in April, 1 8 39.®

To attribute to Reade the discovery of the development of latent
images, as many writers have done , 10 would be to overestimate his
work. Reade saw nothing in the action of the tanning substance but
the quickening of a photographic blackening process, without recog-
nizing in the least the reaction of the latent light image to development
by silver halides.

LINOGRAPHY

Photographic reproductions (mostly enlargements) were produced
on linen, to be afterwards colored, by a variation of Talbotypy (silver
chloride or silver bromo-iodide on linen with gallic acid or pyrogallic
development) . J. Liittgens, in Hamburg, states that he used this process
in 1856. In 1863 Disderi practiced a process in France, which had been
imported from America, in which the portrait was enlarged direct and
colored on linen. Conte Bentiviglio also exhibited, in 1863, life-size
photographs on linen, which were finished in oil colors. Enlargements
by electric light on linen were produced especially by Winter, in
Prague (later in Vienna) (“Linographie,” in Jahrbuch, 1889, pp. 72,
42 1).

ROBERT HUNT DISCOVERS (1844) DEVELOPMENT WITH
PROTOSULPHATE OF IRON

The publication of the processes of Daguerre and Talbot excited the
desire for further study of the action of various developers on the silver
iodide coating, and attention was drawn to photographic developers
acting in aqueous solutions, a process which gradually supplanted Da-
guerre’s development with mercury vapors. The discovery by Robert
Hunt ( 1 844) that iron sulphate (vitriol) was suitable for the develop-
ment of light pictures on iodide, bromide, and chloride of silver was

326 NEGATIVES AND POSITIVES ON PAPER

of great importance for the future. It is well known that it was just this
iron sulphate developer which brought “wet collodion” photography,
invented several years later, to such efficiency.

Robert Hunt (1807-1887) was librarian and keeper of mining rec-
ords at the Museum of Practical Geology and professor of mechanical
engineering at the Royal School of Mines, at London. He carried on
numerous photographic and photochemical experiments and he was
one of the founders of the London Photographic Society. These experi-
ments with organic and inorganic light-sensitive substances, which,
with characteristic unselfishness, he made public during the early forties
of the last century, were extremely useful in the study of photochemis-
try, which was then in its infancy, and were of great service for years
to those who came after him and used his researches for the basis of
their studies. His most important publications are: Robert Hunt, Re-
searches on Light; an Examination of All the Phenomena Connected
with the Chetnical and Molecular Changes Produced by the Influence
of the Solor Rays (1844, 2d ed., 1854) ; A Popular Treatise on the Art
of Photography, (1841, 2d ed., 1847); A Manual of Photography
(1851, 1853, 1854, 1857); The Practice of Photography (1857); and
Poetry and Science (1849), which contains chapters on “Actinism,”
“Chemical Radiations,” and so forth.

In the development of his discovery ( 1 844) that protosulphate of
iron had many advantages over gallic acid as a developing agent for all
papers sensitized with the halide salts of silver, Hunt proposed several
processes. In one of these, which he called “energiatype” or “ferro-
type,” the paper was first floated on a solution of pure succinic acid,
common salt, and gum arabic, dried, and sensitized with nitrate of silver
solution. After exposure, the image was developed with iron sulphate.
Another process he called “fluorotype,” in which potassium bromide
and sodium fluoride were employed. He also improved the process by
Dr. Woods, in which the paper was iodized with syrup of iron iodide
and sensitized with silver nitrate solution, to which process he gave the
name “catalysotype” ( Handbuch , 1898, II, 129).

Although development with iron salts for paper prints and albumen
prints was not very successful, the iron sulphate developer later proved
itself highly useful, after the discovery of the collodion process, by
shortening the time of exposure, which compels us to pay particular
attention to its introduction into photography.

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FURTHER APPLICATION OF CALOTYPY OR TALBOTYPY

In France there was at first very little attention paid to Talbotypy.
A few haphazard experiments, in which the details of the photograph
were destroyed, owing to the roughness of the paper, created the im-
pression that the process had an inherent defect. As a matter of fact,
the daguerreotypes of that time were far superior in detail to the Tal-
botypes. Nevertheless, and justly, Talbot maintained his conviction
that the future of photography must depend upon perfecting a process
for making negatives in the camera, for only thus could the possibility
of multiplying the picture be attained.

The Scottish painter David Octavius Hill devoted himself, in 1843,
to the production of large photographic portraits by calotypy, which
he used as such only or as an aid to portrait painting. Most of his work
was in proportionately large sizes and shows good artistic conception.
Hill’s photographs were held in high esteem in England and Scotland,
which was proved at the Photographic Exposition at Edinburgh, in
1857, where calotypes of Hill and his assistant R. Adamson were exhi-
bited and acclaimed for their artistic conception and execution (Brit.
Jour. Phot., December, 1924), and at Manchester Exhibition (Brit.
Jour. Phot., 1841, p. 346).

A monument to David Octavius Hill was erected in his native town,
Perth, in 1914, and a monograph David Octavius Hill, by Dr. Heinrich
Schwarz, was published, with eighty reproductions of Hill’s calotypes
(Leipzig, 1930).

blanquart-evrard’s improvements

An amateur in Lyon, Blanquart-Evrard, pursued the idea of improv-
ing Talbot’s invention and introducing it into practical photography.
While Talbot added the developer (gallic acid) right at the beginning
to the sensitized coating and poured it over for a second time following
the exposure in order to insure full development of the image, Blan-
quart-Evrard 11 realized that silver bromo iodide with silver nitrate
(without gallic acid) furnished a more sensitive coating for the negative
process and that shorter exposures and clearer images could be obtained
by postponing entirely the application of gallic acid as developer until
after the exposure.

Blanquart-Evrard exposed the wet silver bromo iodide paper with
nitrate solution (without gallic acid) between two glass plates in the

328 NEGATIVES AND POSITIVES ON PAPER

camera and developed immediately with gallic acid. 12

Instead of coating the paper with iodide salts alone, mixtures of salt
were mainly used, mostly iodo-bromine salts; or, according to Cundell,
iodo-chlorine salts; 13 or, according to Le Gray, iodo-cyanide and
fluorite of potassium. 14 Parr added sodium acetate as an accelerator to
the iodo-bromine salt. 15

In the field of photography we are indebted to Blanquart-Evrard
for many improvements, 10 in particular for having introduced the
developing process of iodide bromide (or silver chloride) paper by
gallic acid as a rapid printing process for producing large editions of
silver prints.

Blanquart-Evrard published, in 1852, a guide on Egypt, Nubia, Pal-
estine, and Syria, photographically illustrated from Talbotype paper
negatives.

Blanquart-Evrard’s commercial success was considerable; he opened
a photographic establishment for producing prints in large editions
from photographic paper negatives at Lille, in 1851, and at the same
time another, in Paris, through Chevardiere, which he operated on a
business basis. In England he later associated himself with Thomas
Sutton 17 in establishing (1855), at the request and under the patron-
age of Prince Albert, a photographic printing establishment, where his
rapid printing and developing process was carried on. At the same time
he advanced photography by numerous contributions to technical
publications.

In order to give a synopsis of the important features of Blanquart-
Evrard’s technique in printing, we particularize: The paper was first
immersed for a few hours in a solution of one liter of water, 10 g. of
gelatine, 10 g. of potassium iodide, and 2 '/ 2 g. of potassium bromide,
then dried and subjected under a glass bell to the vapors of hydro-
chloric acid for fifteen minutes. After its removal from these vapors it
was immersed for another quarter of an hour in a 7 per cent silver bath,
acidified with a few drops of nitric acid, whereby a mixture of silver
iodide and silver bromide was formed in its texture. By placing the
sensitive paper between two blotting papers and squeezing it, the excess
of silver nitrate was absorbed and the silver paper, after being dried,
now completely prepared and ready for use, was placed under the
paper negative and exposed to light. Depending upon the density of
the negative, the exposure lasted in diffused daylight for three to twenty
seconds, when the image became slightly visible; it was then completely

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3 2 9

developed in a gallic acid bath for about twenty minutes, but showed
at first a very disagreeable color. The fixation was continued, without
previously having rinsed off the developer, in two successive baths of
five per cent of sodium-thiosulphate (hypo); during the first bath of
five minutes a light toning took place (sulphur toning) ; the second
bath lasted for twenty minutes, then the pictures were dipped into
hydrochloric acid, which removed the yellow precipitate, and finally
were washed and dried.

Calotypy had spread quite universally throughout Germany by
1 842. Dr. F. A. W. Netto published a technical description in his Die
kalotypische Portratkunst (Quedlinburg and Leipzig, 2d ed., 1843, 5th
ed., 1856), and A. Martin in his Repertorium der Photographie (Vi-
enna, 1846-48, 5th ed., 1857).

W. E. Liesegang promoted calotypy in Germany by word and by
the publication of articles. A portrait of Wilhelm Eduard Liesegang
made at Elberfield was reproduced from a calotype on wax paper in
1929 by the firm which he founded, and which in the fifties sold appa-
tus, chemicals, etc. for calotypy and the wet collodion process. 18

Talbotypes were popular for portraits, landscapes, and architectural
subjects in the middle of the last century, and were produced long
after glass negatives had been introduced. Towards the end of the
fifties they had to give way, finally, to the collodion process on glass.

Good Talbotypes were made in England in large numbers by P. H.
Bird ( 1851), R. R. Turner, and others in the beginning of the fifties.
A fine collection of calotype paper negatives, made by Charles Mar-
ville, France (1854), was presented by Mr. Pricam, of Geneva, to the
Graphische Lehr- und Versuchsanstalt, Vienna, at the request of Dr.
Eder. In size they average 27 x 36 cm. (10% x 14 1 / inches). Other
Talbotypes were exhibited at the World Exposition of 1862, at Lon-
don. Talbotypes were also made in other countries of Europe and even
in the Orient.

About this time the French photographer Martens executed a pano-
rama of Mt. Blanc, in fourteen parts, on Talbotype paper, taken at a
height of 1877 meters (6,158 feet). This was probably one of the first
panoramic views produced by this method.

While France and England were the centers for photography in
western Europe, Vienna became the center in eastern Europe, where
there arose amateurs, such as the librarian Martin, at the Polytechni-
kum, and the scientist Ettingshausen, at the University of Vienna.

NEGATIVES AND POSITIVES ON PAPER

33 °

It became, so to speak, the source from which numerous students of
photography migrated to the eastern countries of Europe, in particular
to the lower Danubian states, such as Serbia. A characteristic example
of the work of one of these pupils is the halftone reproduction of a
paper negative made by Jovanovits, 19 in Belgrade (1858). Specimens
of such well-preserved Talbotype paper negatives are now very rare,
since they were made in large numbers only in the fifties of the last
century and were replaced as early as the end of the fifties and the
early sixties by wet collodion negatives on glass. This process undoubt-
edly gave greater detail and softness; in recent years photography in its
most modem form has reintroduced negative and positive emulsions
on paper and film with undreamt-of possibilities in their practical appli-
cation.

DEVELOPMENT WITH PYROGALLIC ACID BY REGNAULT AND
LIEBIG (1851)

It must be emphasized that the methods of development employed
at this time (gallic acid and silver nitrate) comprised only the so-called
“physical development,” that is, it consisted of pouring a solution of
silver nitrate and gallic acid, which had a slow reducing action (espec-
ially following the usual acid treatment with acetic acid), on the
exposed iodide-bromide (or chloride) of silver; this compound decom-
posed slowly, precipitating powdered metallic silver, which adhered
in its nascent state to the portions which represent the image; this
same principle applies to the collodion process.

The important observation that pyrogallic acid, discovered by
Braconnot in 1831, is a much more energetic and rapid photographic
developer than gallic acid was made by the physicist Regnault, 20 pro-
fessor at the College of France, in Paris, and the chemist Justus Liebig,
at the University at Giessen each independently from the other and
simultaneously in 1851. Regnault developed his paper negatives with
an aqueous pyrogallic acid solution (1:1,000), and exhibited his pho-
tographs early in 1851 at the “Societe Heliographique,” in Paris, where
they attracted particular attention, owing to their vigor and the beau-
tiful modulation of the middle tones. 21 Liebig attained the same results
independently. 22 Thus was accomplished an important step in the
shortening of exposure by the use of more energetic or “faster” devel-
opers. 23 Pyrogallic acid was used as a developer in Talbotypy and
Niepceotypy and in the beginning of the wet collodion process. Later

EARLY PROCESSES AND THE GRAPHIC ARTS 331

it had to give way to the iron sulphate developer in the latter process;
but it remained as an intensifier (see silver intensification of collodion
plates) and gained increased importance later through its successful
application as an alkaline developer in the dry-plate process.

APPENDIX

ROLL HOLDERS AND ROLLER DARK-SLIDES FOR NEGATIVE PAPERS

The frequent use of calotype paper in landscape photography
brought the traveling photographer early to the use of rolled sensitive
negative papers. Thus we find Captain Barr (1855) describing the roll-
holder for sensitized paper of the Englishmen Joseph Blakey Spencer
and Arthur James Melhuish (1854); also a similar holder by Relandin
was exhibited to the Photographic Society, in Paris, 1855. This latter
could be filled or loaded in daylight.

From this was developed Warnerke’s roll-holder (1875), with a
silver-bromide collodion stripping emulsion, and the “roll-holder” of
Eastman- Walker for the bromo-silver gelatine stripping paper and,
later, films (see Chapter LXVI) .

Chapter XXXVIII. reaction of the in-
vention OF THE DAGUERREOTYPE, THE TALBO-
TYPE, AND THE EARLIER PHOTOMECHANICAL
PROCESSES ON THE MODERN PROCESSES OF THE
GRAPHIC ARTS

Daguerreotypy produced merely single picture images, which could
be multiplied only with the greatest difficulty; nevertheless, daguerreo-
types of landscapes and architectural subjects were at first welcomed as
original copy by illustrators, in particular for reproduction as litho-
graphs and steel engravings. Such publications of the forties and the
fifties of the last century are numerous, and they show a splendid
schooling in the conception of perspective and true form.

It was the introduction of Talbot’s negative process that made photo-
graphic illustrations and the reproductions of art subjects accessible to

332 EARLY PROCESSES AND THE GRAPHIC ARTS

the general public, because it facilitated a purely photographic repro-
duction process.

One of the first publications illustrated in a purely photographic
way is T albot’s T he Pencil of Nature ( 1 844) , with twenty-four photo-
graphic silver prints. In this publication Talbot made subjects of all
kinds accessible to the reading public.

Blanquart-Evrard was the first to recognize that the process of mak-
ing prints on silver chloride paper was too slow for illustrating books;
he therefore introduced into practice the more rapid method, employ-
ing iodo-bromide paper with gallic acid development as better adapted
for the production of prints in quantities. 1

Blanquart-Evrard, jointly with an artist friend, Hippolyte Focke-
dey, published, in 1851, an Album photographique de F artiste et de
P amateur. More important was the book on travel entitled Egypt, Nu-
bia, Palestine and Syria (1852), photographically illustrated, for which
Du Camp made the paper negatives and from which Blanquart-Evrard,
in Lille, made the prints for the work. This incunabulum of photog-
raphy, of which only twenty copies were printed, has long since dis-
appeared from the book markets. 2 The positive paper pictures were
developed by Blanquart-Evrard in Lille (1852) with the gallic acid
developer, and today they are better preserved than other prints on
silver chloride paper, which were produced by printing-out without
development. A second work of Maxime du Camp, Souvenirs et pay-
sages d'Orient, is still extant; it contains photographs and was pub-
lished in 1851.

Another successful photograph is the picture of a Flemish windmill
from a paper negative by Blanquart-Evrard, reproduced in La Lu-
miere (July, 1 855, p. 1 1 5) . These two examples suffice to illustrate the
status of photography at this date.

At this time, also, August Salzmann. in Jerusalem, published a work
on the Holy City and its monuments (Paris, Gide et Baudry), with
one hundred and eighty full-page illustrations, for which credit is
given to the “Imprimerie photographique” of Blanquart-Evrard, in
Lille. 3

Photographic illustrations for books and periodicals, of course,
found their modern application only when the photomechanical proc-
ess had been so far developed that they could be printed with printing
ink on copperplate and, later, typographical presses.

We shall mention at once the beginning of book illustrations by the

EARLY PROCESSES AND THE GRAPHIC ARTS 333

photomechanical method, although in doing so at this time we antici-
pate the course of its historical development.

The first printed matter, known to us, illustrated by a photome-
chanical method is Berres’s brochure on daguerreotype etching Photo-
typ nach der Erf indung des Prof. Berres in Wien (Vienna 1840) , with
five illustrations and two pages of text. It contains an illustration of the
dome of the St. Stephan Church, in Vienna, and two other architectural
views of it, a reproduction of a copperplate engraving, and a mezzo-
tint.

This pamphlet, however, was printed in a small edition, because the
plates could not stand more than two hundred impressions, and the
size of the illustrations was small. On the other hand, the periodical
founded by Paul Pretsch during his stay in London entitled Photo-
graphic Art Treasures; or, Nature and Art, Illustrated by Art and
Nature, published by the Patent Photo-Galvanographic Company,
London, December, 1856, was probably the first work of large size,
illustrated by a photomechanical process and printed from intaglio
copper printing plates. The size was enormous, considering the con-
ditions then prevailing, that is, 38 x 55 cm. (15x21% inches). I have
before me two volumes (1856 and 1857) with nineteen full-page in-
serts of the most varied subjects, which are reproduced in an excellent
manner by Pretsch’s process of copperplate printing. I dare say it is
probably the first experiment in publishing an illustrated periodical
devoted to the arts, executed in de luxe style with inserts produced by
photographic printing plates. The illustrations in the text, printed from
plates made in the halftone manner, were successfully inserted in the
type forms; many similar publications covering various fields soon fol-
lowed, but this is not the place to go farther into this matter. The his-
tory of the invention of the photomechanical illustrating processes
(Berres, Poitevin, Talbot, Pretsch, and others) is treated exhaustively
in later chapters of this work.

Chapter XXXIX. bayard’s direct paper

POSITIVES IN THE CAMERA AND ANALOGOUS
METHODS

Hyppolite Bayard (1801-1887), amateur photographer and official
of the Ministry of Finance at Paris, invented independently of Talbot,
an original process on silver iodide paper, in May, 1839, a month
before Daguerre made his invention public. It differed from Talbot’s
calotype process principally because it produced positive images
directly in the camera.

The Moniteur officiel of June 24, 1839, contains a description of
such pictures made by Bayard, in Paris; 1 one of these shown by Poton-
niee in his Histoire (1925, p. 207) gives Bayard’s portrait and a de-
scription of his process, together with proofs of his work.

H. Bayard had occupied himself for a long time previously with
experiments in photography and had published his photographic pro-
cess, which produced direct positive images in the camera, after Arago
had made his preliminary report on daguerreotypy in January, 1839.
Talbot’s process had not yet been made known. On February 5, 1839,
Bayard showed some very crude specimens of his method to Desprets,
member of the Academy, and to Biot on May 1 3, and to Arago a week
later. He required an hour’s exposure for the production of his paper
images. Bayard kept his method secret then, but delivered a descrip-
tion of it to the Academy of Sciences in a sealed letter on November
11, 1839. The pictures themselves, which, of course, were not portraits,
were exhibited by Bayard in Paris, June 24, 1839, and were favorably
mentioned in the French journals of July and August, 1839. Some of
his pictures are still preserved by the French Photographic Society,
of which body he was for years the secretary.

Bayard’s process was not made public until February 24, 1840
( Compt . rend,., 1840, I, 337). It consisted in exposing silver chloride
paper which had been blackened by light and immersed in a 4 per cent
potassium iodide solution, while still moist, in the camera; the portions
acted on by the light would then be bleached (separaton of iodine
from the potassium iodide and combination with the blackened silver
image); thus a direct positive image resulted in the camera.

Bayard and his friends attempted to gain recognition from the
government for his invention, but without success, because his process,
though interesting in theory, could not compete with daguerreotypy.
On the day that Bayard made his public announcement before the

DIRECT PAPER POSITIVES

335

Academy, V erignon also brought before it the description of a similar
process; and a few days later Lassaigne recalled to the members that
a year earlier he had communicated this process to them. A contro-
versy, in which Arago participated, started as to the rights of priority
in the invention. He reported his conclusions on the history of this in-
vention at the session of the Academy of March 1 6 , 1840, and called
attention to the fact that the photographic methods of Verignon and
Bayard do not differ from the same process of Lassaigne, which had
been announced in the journal L'Echo du monde savant on April 10,
1839, and was described in the Compt. rend. (1840, pp. 336-37, 374,
478). An Englishman, Fyfe, also had described the same method before
the Society for Arts, at Edinburgh, April 17, 1839 ( Edin . New Philos.
Journ., 1 839, p. 1 14) . While Lassaigne and Bayard used silver chloride
paper, Fyfe employed a paper prepared with chloride or phosphate
of silver; 2 he blackened the paper in light and coated it with potassium
iodide solution, 1:30; this faded in the light and the blackened silver
coating of the paper showed a positive image when exposed under a
copperplate engraving.

If priority of publication of the process is to decide whose claim is
valid, Lassaigne must be mentioned first, then Fyfe, and only then
Bayard and Verignon. Hunt also studied this phenomenon later and
a great deal more exhaustively than those named above.

Herschel also mentions a similar method. He prepared paper with
lead acetate, potassium iodide, and silver nitrate, allowed it to blacken
in the sun, and dipped it in a potassium iodide solution, whereupon
the sun bleached the paper (Phil. Trans., 1840, Article 48). Grove
made the same observation with some of Talbot’s blackened calotype
paper; this method proceeded best, according to Hunt’s statements,
behind violet glass. 3 Poitevin also described this same bleaching method
in October, 1 8 59, using silver iodide wet collodion plates with numer-
ous modifications (Bull. Soc. franp. phot., 1859, p. 314). A composite
report on this method is found in Martin’s Repertorium der Photo-
graphie (1846, pp. 17, 25, 63, 74, and in later editions). A detailed
description of the theory and practice of this and allied processes down
to modern times is given in my Handbuch (1884, II, 47).

APPENDIX

Karl Emil Schafhautl ( 1 803-1890), Doctor of Philosophy and Medi-
cine, who lived several years in England, announced a method which
was supposed to lead to the production of direct positive photographs

BREYEROTYPY

33<5

in the camera; he allowed silver chloride paper to blacken in light,
dipped it in a solution of mercuric nitrate, which was to produce
bleached-out pictures (Dingler’s Polytechn. Journ., 1840, LXXVIII,
238).

The method is absolutely useless, which caused the present author
to omit it from the previous editions of this history. It emerges, how-
ever, from the obscurity it deserves every once in a while in historical
notes and without comment on its uselessness. It was discussed by
Erich Stenger in Phot. Ind. (1926, No. 14).

Chapter XL. reflectography (breyero-

TYPY) BY ALBRECHT BREYER, 1839

When the first news on Daguerre’s invention reached Belgium, in
1839, Albrecht Breyer, of Berlin 1 a medical student at the University
of Liege, occupied himself in finding a process for printing photo-
graphs. He did not so much intend to fix the photograph obtained
in the camera, as to endeavor to obtain exact impressions from engrav-
ings, drawings, and pages printed on both sides, without the use of a
camera. Five days before the memorable session at which Arago re-
ported to the Paris Academy, on August 19, 1839, the detailed descrip-
tion of daguerreotypy, that is, on August 14, 1839, Breyer submitted
his photographs to the Academy of Science in Brussels. It was not,
however, until October 6, that Breyer’s specimens were revealed to the
session and not until November 9, 1839, that the original report of
Breyer was made known to the Academy at Brussels.

Breyer, incited by the first general news of Daguerre’s invention,
immediately began to experiment with silver chloride paper, and he
observed accidentally reflect manifestations. Placing a piece of silver
chloride paper with its sensitive surface in contact with a printed page,
he let the light shine through the back of the paper and was astonished
to find the clear type reproduced in reversed position, that is, a nega-
tive impression, showing white lettering on a brownish black back-
ground. At the end of March, 1839, he succeeded in making “helio-
graphic pages” of this kind, which he showed to different persons and
were reported by the journal L’Espoir, April 9, 1839. It seems that he
also fixed these silver chloride prints, for he mentions the usefulness

BREYEROTYPY

337

of these reflectographs for the multiplication of type matter and simi-
lar designs in considerable quantities, if one wished to use the first
(negative) copy for this purpose. He was aware of the commercial
value of his invention, and he emphasized the possibility of producing
copies of written and printed matter, even on perfectly opaque pages,
without the use of a camera.

He was also aware of the scientific basis for his process for he states
in his report:

When heliographic papers are placed in a specific manner on the copies
(drawings, etc.), the largest part of the light penetrates these papers . . . ;
and, arriving at the opaque parts (of the type, etc.), is reflected by the
white parts (of the paper) and absorbed by the black parts. It is by this
combined action that I explain the phenomenon, which in this case makes
the image appear on the inner surface of the heliographic papers.

This discovery of Breyer’s was first briefly referred to by Helmer
Backstrbm in the Norilsk Tidskrift for Fotografi (Stockholm, 1923,
VII, 36) and later in Camera, (Luzern, 1923, 1 , 218).

For the most thorough account of Breyer and the Breyertype ex-
periments we are indebted to Erich Stenger (Phot. Indust., 1925, No.
47, and 1926, No. 7). These early statements about Breyertypes were
very vague and attracted very little attention, the more so because
Breyer himself does not seem to have concerned himself further in the
matter.

The records of the Academy at Brussels, however, prove indisput-
ably that Breyer discovered, in 1839, this process of reflectography,
which was later brought to practical use in playertype (with gelatine
silver bromide) 2 and in the Manul 3 process (with chrome gelatine) and
other various modifications, all of which are based on the principles of
Breyer’s method (Handbuch, 1922, IV(3), 386, “Heliogravure”),
where the evolution of this process is described in detail.

F. N. Feldhaus questioned whether Breyer should not be regarded
with Daguerre as the inventor of photography. The question must be
definitely answered in the negative. He is not the inventor of photog-
raphy, but undoubtedly the inventor of an important photographic
method of obtaining facsimile copies of opaque designs without the
use of the camera, and his invention has had many useful applications
in modern photo-reproduction.

Chapter XLI. photographic negatives

ON GLASS (NIEPCEOTYPES)

The art of producing images on glass was invented by Niepce de
Saint-Victor, in 1847. 1 This method was called Niepceotypy in his
honor, but the name “glass negatives” soon became more popular. When
the completely transparent glass replaced paper, much more beautiful
negatives were obtained than could be made on the more or less coarse-
grained paper, for in the middle of the last century paper could not
be manufactured with such a fine structure as at the present time.

Claude Felix Abel Niepce de Saint-Victor, born 1805, in Saint Cyr
near Chalon-sur-Saone, was the cousin of Nicephore Niepce, although
he always addressed him as “uncle.” He attended the school for cavalry
at Saumur and became Lieutenant of Dragoons in 1 842 . The accidental
discovery that a vinegar spot on his madder red uniform could be re-
moved by ammonia and that the madder color was made brighter by
the treatment interested him in dye experiments. As a result, he re-
ported a simple receipt to the military authorities for the brightening
up of faded red uniforms, and this brought official support to his ex-
periments.

In 1 845 he was transferred to the Paris Municipal Guard, quartered
in the barracks of the suburb of Saint Martin, where he equipped a
chemical laboratory. His first work, presented to the Academy of
Sciences at Paris, October 25, 1847, 2 dealt with the condensation of
iodine vapors on a copperplate engraving and the reproduction of the
iodine vapor image onto metal.

He was evidently unaware of the earlier publication of J. J. Pohl’s
(Vienna) on the discovery of atmography with iodine vapors; in both
cases the phenomena are similar, but Niepce de Saint-Victor carried his
observation to a practical application ( Handbuch , 1922, IV (3), 392,
under “Atmographie, Heliogravure,” etc).

Niepce de Saint-Victor made his important invention of photog-
raphy on glass in 1 847. The barracks in which he lived were burned in
February, 1 848, and his laboratory and all his apparatus was destroyed.
He became Captain of his regiment in 1 848, returned to Paris and the
“Garde Republicaine” in 1 849, was elected Chevalier of the Legion of
Honor and received also a prize of two thousand francs from the So-
ciete d’Encouragement. He improved the asphaltum process of his
cousin Nicephore Niepce and greatly advanced photointaglio etching
on steel. In his works Recherches photographiques and Traite pratique

NIEPCEOTYPY

339

de gravure heliographique sur acier et sur vet re (Paris, 1858), are con-
tained portraits of Niepce de Saint-Victor, etched on steel after Rif-
fault’s process. Urged by Alexander Edmond Becquerel (1848), he
then took up heliochromie and heliogravure with asphalt (1853-1855).
Appointed Squadron Leader and Commander of the Louvre in Paris,
he now had time for his experiments and investigated, among other
subjects, photography with uranium salts. 3 He was pensioned when
Napoleon III came to the throne, and in his retirement he continued
untiringly and unselfishly his researches in scientific photography; he
died in 1870.

INVENTION OF PHOTOGRAPHY ON GLASS

Early in 1847 Niepce de Saint- Victor experimented with the use of
starch paste on his glass plates as a binding substratum for the iodide
coating, but he soon found that albumen was preferable; he also tried
gelatine, but laid it aside because it came off in the aceto-silver nitrate
bath. By a mixture of honey, syrup, or whey with the albumen, he in-
creased, later, the sensitivity. He published his process on October 25,
1847, in the Compt. Rend., and he soon had many followers. He also
made many modifications.

De Brebisson added dextrine to the albumen and gum arabic, and
many changes developed in the process ( Handbuch , 1927, Vol. II,
Part 3).

Niepce de Saint-Victor, after obtaining fresh albumen (white of
egg), mixed with it potassium iodide, coated the plate and dried it, then
immersed it in the silver nitrate bath, in which the albumen coagulated
and remained on the glass as a homogenous coating. After exposing the
plate, he developed it with gallic acid, for which he later substituted
pyrogallic acid ( Handbuch , 1927, 11(3), 60).

These photographic “glass pictures,” called “Niepceotypes,” gave
structureless, transparent negatives, and the process quickly became
popular. Blanquart-Evrard 4 described, in 1849, a process very similar
to that of Niepce de Saint-Victor, with minor changes, and called at-
tention to the fact that the silver-iodized albumen could be used either
moist or dry. He also invented the so-called “amphitype” process 5 and
produced an underexposed Niepceotype on a dark background, which
when looked at on the coated side showed as a positive, but from the
back of the glass appeared as a negative. Blanquart-Evrard described
his “epreuves amphi-positives” in La Lumiere (September 3, 1856),
and laterin the Bull. Soc. franp. phot, (i860, p. 5).

NIEPCEOTYPY

340

Talbot modified the method for negative making in 1851. He first
albumenized and silvered the glass plate; then, after flowing over it a
second albumen solution, to which he added ferrous iodide, he dipped
it again in a silver bath. He took out an English patent on this method,
June 12, 1851. The sensitivity of the plate was so great that he was able
to produce with it the image of a piece of printed matter pasted on a
rapidly rotating disk with an instantaneous exposure by the light of an
electric spark.

Le Moyne substituted iron vitriol (iron sulphate). 6 Le Gray 7 used
neither iron sulphate nor pyrogallic acid. His publications disclose the
considerable application of the albumen process by the early fifties to
the production of stereoscopic glass positives and lantern slides.

Two German- American photographers, the brothers W. and F.
Langenheim, of Philadelphia, were the first to introduce glass projec-
tion pictures or small transparencies (lantern slides) ; in 1846 they im-
ported from Vienna a projection apparatus and slides. In the winter of
1846-1847 they remodeled their apparatus for the reproduction of
daguerreotypes; these were illuminated by two oxygen burners, and
the picture was projected onto the wall through large lenses. In 1 849
they began to make their own slides, and they gave public exhibitions
of their productions in Philadelphia in 1850 and 1851 (Brit. Jour.
Phot., 1865, p. 318). These slides were made by Niepce de Saint-Vic-
tor’s albumen process, which they patented in the U.S.A. under the
name of “hyalotypes,” in 1850; they published a catalog of their dia-
positives in the same year. Robert Hunt approvingly discussed these
Niepceotypes in the Daguerreian Journal (April 15, 1851). Soon after-
ward, in France and elsewhere, these glass diapositives, or others of a
similar kind, were made by the Taupenot collodion albumen process
(see Chapter XLVII), until all these earlier processes were superseded
by the silver bromo-chloride and chloro-bromide silver gelatine emul-
sions after 1870.

Of interest here is the work of Alphonse Louis Poitevm, who worked
along the line of introducing gelatine into the negative process, but
unfortunately with such sensitive coatings as silver iodide and with a
gallic acid developer, both of which are especially unfavorable in their
behavior towards gelatine; he missed the importance in certain cases
of gelatine as a binder for photographic silver salt coatings.

Poitevin coated a glass plate with a gelatine solution; after cooling it
off, he dipped it in an acid solution of silver nitrate and dried it com-

NIEPCEOTYPY

34i

pletely, while protected from light. Before exposure, it was subjected
to iodine vapors, just as a daguerreotype plate would be; some time was
allowed to pass, to enable the plate to become more light-sensitive, and
then it was backed with a piece of black cloth and placed in the camera.
The sensitivity of these coated glass plates was much less than that of
the iodo-bromide daguerreotype plate. In order to make the images
visible, the glass plate was immersed from one to one and a half hours in
a 1 / 1 o per cent solution of gallic acid or iron sulphate. It was fixed with
sodium thiosulphate ( Compt . rend,., XXXIII, 647; Jahrb. f. Cbem.,
1850, p. 196; Poitevin, Traite des impressions, 1883, p. 53).

In itself Poitevin’s negative method with gelatine coating was of no
practical value, it is only of interest as the precursor of the modern
gelatine plates.

All these methods soon disappeared again from photographic prac-
tice. They did not provide sufficiently sensitive material, did not re-
duce exposure to any extent in comparison with the daguerreotype,
were cumbersome in their manipulation and uncertain in results. The
albumen process lasted longest, not as a negative process, it is true, but
for the production of transparencies and lantern slides. It is worthy of
note that Lippmann, the inventor of photography in natural colors by
the interference method, used the albumen process in his early experi-
ments, on account of the fine grain of the silver image.

It was only when the wet collodion process developed that the
method of making negatives was entirely transformed and daguerreo-
typy definitely displaced, not only on account of the shorter exposure
made possible, but also owing to the extraordinary fineness of the detail
obtained, and the possibility of rapid multiplication by photographic
printing processes.

During this period of transition from daguerreotypy to photography
with paper negatives and to the wet collodion process daguerreotypy
died, without having had any influence in later years on the revolu-
tionary changes in the progress and process of photography.

Chapter XLH THE WET COLLODION PROC-
ESS

HISTORY OF GUNCOTTON (PYROXYLIN) AND COLLODION

Before the properties of pyroxylin were known, Braconnot had, in
1833, produced a highly inflammable substance, “xyloidin,” 1 by the
action of nitric acid on starch.

Christian Friedrich Schonbein (1799-1868), at Basel, discovered
guncotton in the beginning of 1 846, when investigating the behavior
of nitric acid towards organic substances . 2 Bottger, in Frankfurt a. M.,
heard of this preparation and in August, 1846, 3 arrived independently
at the same process of producing guncotton as that of Schonbein.
Schonbein and Bottger joined forces in order to utilize the practical
advantages of the new substance.

Shortly thereafter Knop, in Leipzig , 4 and Kamarsch and Heeren 5
independently of him, found that in place of nitric acid a mixture of
nitric acid with sulphuric acid could be used. Later Millon and Gaudin
demonstrated 0 that in place of nitric acid a freshly prepared mixture
of potassium or sodium nitrate with sulphuric acid could be used, and
it was also found that other kinds of cellulose, such as paper , 7 linen
fibers, straw, wood 8 and the skin of cactus 9 react in the same manner.

DISCOVERY OF SOLUBLE GUNCOTTON AND COLLODION

The solubility of certain kinds of pyroxylin was discovered first by
Baudin, in 1846, but since he accomplished no practical results, his dis-
covery was forgotten; it was rediscovered in 1847 by Flores Domonte
and Menard, 10 and probably at the same time by Meynard and Begelow.
The solution is named after the Greek word to stick or to

adhere.

Louis Menard is usually called the real inventor of collodion. He was
one of the most genial and eccentric Bohemians of the Latin Quarter in
Paris. Born in 1 822, he entered the Ecole Normale, the school in which
college professors were trained. Because Greek was not taught there,
he left and wrote dramas on the ideology of ancient Greek life. Then
he turned to chemical experiments and worked with guncotton with
Flores Domonte. Jointly they discovered that certain kinds of guncot-
ton were soluble in ether-alcohol, and in 1 847 they invented collodion,
which later became of the greatest importance in photography. They
published their discovery in the French Academy of Sciences ( Compt .

THE WET COLLODION PROCESS

343

rend,., XXIII, 1687; XXIV, 87, 390). Menard placed little value on his
invention and made no effort to realize on it, while an American student
of similar name, Meynard, and an associate, Begelow, made the same
invention shortly after and used it with material success. Menard en-
tered politics in 1848, wrote poetry, and received his doctor’s degree
in philosophy at the Sorbonne in 1852. He disappeared from Paris and
turned up in Barbizon at the school for painters, where Millet also
worked. He took up landscape painting and carried it on for ten years.
Then he turned back to the study of Greek, went to London, and twen-
ty-five years later we find him again in Paris, where, through the in-
fluence of political friends, he was appointed professor of history. He
published Dreams of a Heathen Mystic, of which a new edition ap-
peared in 19 1 1. 11 He moved through the streets of Paris dressed as a
philosopher of the old Greek Cynic School, in wooden shoes, from
which straw peeped out. In his last years he changed completely in his
religious and political ideas and became a fervent Catholic, endeavor-
ing to bring about a union between Christianity and hellenic paganism
( Le Temps, 1911).

Andemaos, in Lausanne, discovered, in 1855, that thick collodion so-
lutions were suitable for drawing out into threads (Br. pat., No. 283,
1855).

CHEMICAL COMPOSITION OF GUNCOTTON AND COLLODION
COTTON

Domonte and Menard gave, in 1847, the first information on the dif-
ference between the chemical composition of ordinary guncotton in-
soluble in ether-alcohol, and collodion cotton, which is soluble in it.
Credit is due them for having recognized that the insoluble guncotton
has a higher content of nitrogen than the soluble collodion cotton.
Gaudin made the same distinction ( Compt . rend., XXIII, 980, 1099;
Journ. f. prakt. Chem., XL, 421).

Their analyses, however, were inexact and produced no useful for-
mula. They were followed by the analyses of Schonbein, Pelouze, Peli-
got, Crum, Abel, Wolfram, and others, whose results, however, dis-
agreed. J. M. Eder made, in 1879, a thorough investigation of the dif-
ferent kinds of guncotton or nitrocellulose, with particular reference
to photographic collodion ( Sitzungsberichte d. Akadem. d. Wissensch.
im Wien, Abteilg. 11 , Vol. LXXIX, March, 1879) .

The formula for cellulose was given at that time as C 8 H 10 O B , and the

THE WET COLLODION PROCESS

344

collodion cotton summed up as C 0 H 8 O 3 (NO 3 ) 2 . Eder demonstrated
in 1879 that the formula for cellulose must be doubled, in order to ex-
plain the properties of the various kinds of nitrocellulose produced and
used for collodion photography.

The analyses gave for the insoluble guncotton, the composition as
cellulose hexanitrat, C 12 H 14 04(N03) e ; for nitrocellulose, difficult to
dissolve, which produces a viscous collodion, the formula of pen-
tanitrate, C 12 H 16 0 5 (N 0 3 ) 5 ; for the normal collodion cotton, cellulose
tetranitrate, C 12 H 16 0 6 (N 0 3 ) 4 ; for collodion cotton rendering a very
easy-flowing collodion, cellulosetrinitrate, which also plays a certain
role in the collodion emulsion process; while cellulose dinitrate,
C 12 H 18 0 8 (N 0 3 ) 2 , gives useless brittle layers. In order to explain these
various properties, we must accept the formula for cellulose as at least
C 12 H 20 O 10 . The author demonstrated that collodion containing am-
monium iodide, and so forth, gradually denitrated and thus became
a thin liquid which produced very brittle coatings. As a by-product,
he called attention to a small amount of a gummy substance, soluble
in water and containing nitrogen, which could influence the sensitivity
of the collodion emulsion ( Handbuch , 1927, 11(2), “Kollodiumver-
fahren”).

THE COLLODION PROCESS IN PHOTOGRAPHY

The history of the discovery of the photographic collodion pro-
cesses was first written by the author of this work in its first edition
(1884) on the basis of studies of the sources. Later historical descrip-
tions were published by others, in which, among other subjects, the
history of photography with collodion was wrongly described.
Schiendl 12 reproduces the names of the inventors of collodion pho-
tography, as well as the surrounding circumstances, incorrectly. This
makes it necessary to go here into this important period of the history
of the development of photography more thoroughly.

In the field of photography Gustave Le Gray 13 was the first to
employ, in June, 1850, a solution of collodion cotton in ether, which
when poured on glass furnished a transparent film which served as a
carrier for the photographic image. He describes this in a very obscure
manner in his pamphlet, published in 1850, Traite pratique de photog-
raphic sur papier et sur verre:

I invented a method with collodion on glass with hydrofluoric acid meth-
yl ether, potassium fluoride, and sodium fluoride dissolved in a 40° al-
cohol, mixed with ether and saturated with collodion; I then sensitized

THE WET COLLODION PROCESS

345

■w ith acid silver nitrate and obtained in this manner images in the camera
obscura with twenty seconds exposure in the shade. I developed the
image with a very weak solution of iron sulphate, and fixed with hypo-
sulphite. I hoped to achieve with this process a very great sensitivity. By
the use of ammonia and potassium bromide I obtained great variations in
the results.

Le Gray’s formula is practically impossible of execution, because
potassium fluoride is not a photographic agent and hydrofluoric acid
ether was not known at all. Therefore Le Gray has merely the dis-
tinction of having been the first to call attention to the possibility of
the use of collodion in photography. It does not seem possible to obtain
successful photographic results in accordance with the above state-
ments of Le Gray.

Gustave Le Gray was a French painter who endeavored to improve
his financial position by opening a photographic studio. Poitevin is
supposed to have induced him to do this. While his atelier at the
Barriere de Clichy did not prosper to any great extent, he spent a good
deal of his time in producing negatives on glass and had the idea of
substituting collodion in place of albumen or gelatine as a base for the
silver iodide coating. Although his first directions for the collodion
process were extremely uncertain, he succeeded shortly in producing
thoroughly good collodion negatives with relatively short exposures;
it appears that he soon worked with the improved iodide collodion,
which he describes in the second edition of his book (1851). 14 His
photographic studio did not succeed, owing to lack of business, and
he gave it up. Leaving Paris, he went to Egypt, painted for some time,
and finally became instructor of drawing in a Cairo school. Misfortune
followed him; while riding on horseback, he was thrown off, broke
a leg, and died shortly afterward, in 1882.

The credit for having been the first to make the collodion process
known in an intelligent manner and to give practical directions for
its use belongs to Frederick Scott Archer (1813-1857). He turned his
attention to collodion in 1849 and published an article on the wet
collodion process, as it is generally used today, in The Chemist (Lon-
don), March, 1851. He produced a large number of very beautiful
collodion negatives. Archer and Le Gray entered into a controversy
as to their respective rights to priority in the invention of the collodion
process, which dragged along for several years. Le Gray tried to es-
tablish his right to priority in the second edition of his T raite pratique

346 THE WET COLLODION PROCESS

de photographie sur papier et sur verre (1851), by claiming that he
had used collodion before Archer, but accident played him a mean
trick. The typesetter read instead of “avant M. Archer,” “avant de
marcher,” and so the world learned with astonishment that Le Gray
used the collodion process before M. Archer could walk. Not until
1854 was Le Gray in the position to correct this printer’s error.

Archer insisted strenuously on his rights to priority and tried to
prove his claim in the Liverpool and Manchester Photographic Journal,
(1857, p. 1 2 1 ) , 15 in which he was supported by the testimony of his
wife Fanny Archer. 18

Archer’s partisans gave the collodion process the name “Archero-
typie” (or Archertype), proposed by Belloc. 17 At any rate, Archer,
as well as later two other Englishmen, P. W. Fry and Robert J. Bing-
ham, deserve credit for the introduction of the process into practice
(see Photogenic Manipulation by Robert J. Bingham, 1850).

Bingham also, notwithstanding Le Gray’s and Archer’s superior
claims, tried unsuccessfully to appropriate the priority forthe discovery
of the collodion process, 18 although later he claimed that he had worked
with collodion since 1851. Notwithstanding this, great credit is due to
Bingham for his article, “On the Use of Collodion in Photography,”
in which he impressively points out the photographic properties and
advantages of collodion. 19 In 1851 he was sent by the British govern-
ment to Paris to photograph the prize-winning industrial exhibit at
the exposition of that year. He produced twenty-five hundred photo-
graphs in a very short time by the collodion process, which created
such a sensation that all photographers hastened to throw aside da-
guerreotypy and to introduce the new process. 20

F. Scott Archer also invented the stripping of collodion films by
coating the negative with a rubber solution, which enabled the nega-
tive films to be preserved without the glass plate; he took out an Eng-
lish patent for this invention (August 24, 1855), which later found
numerous varieties of application in heliogravure and for direct print-
ing on metal for subsequent etching.

Frederick Scott Archer died in May, 1857, without leaving any
material means, and his contemporaries in England raised a purse of
seven hundred forty-seven pounds sterling by subscription for his
wife and children, to which the government added an annual pension
of fifty pounds sterling for the children. The motive is stated to be that
their father “was the discoverer of a scientific process of great value to

PHOTOGRAPHY AS AN ART

347

the nation, from which the inventor had reaped little or no benefit”
(Harrison, A History of Photography, 1888, p. 40).

Millet, in 1854, was the first to produce positives on enamel with
collodion, which he exhibited at the French Academy of Sciences. 21

As photography with the collodion process spread throughout the
world, a great demand sprang up for guncotton and suitable iodide
and bromide salts. The chemicals needed were at first purchased in
apothecary shops, but gradually special business places for the sale of
photographic materials were established. We mention here only the
firm A. Moll, in Vienna, which was combined with the court phar-
macy, and the firm Liesegang, in Germany, where also the old “Griine
Apotheke,” in Berlin, sold photographic chemicals and which was in
1881 absorbed into the Schering’s Chemical Company. This firm pro-
duced in 1878 a special grade of collodion cotton which corresponded
to the cellulose nitrate, and which was purified by washing in diluted
sulphurous acid ( Handbuch , 1927, II, 30). The trade name given to
this cotton was “Celloidin Cotton,” and the name of the first German
collodion silver chloride photographic printing papers was “Celloidin
Papers” ( Handbuch , 1928, IV(i), 228).

In 1856 Dancer, in Manchester, was the first to reproduce very small
portraits and manuscripts legible only under the microscope by the
collodion process. 22 Even before this, the collodion process was used
in the production of photographic enlargements from microscopic
originals.

During the fifties the collodion negative process spread to such an
extent that it was generally practiced in the early sixties, together with
the iron sulphate developer, which gave such splendid results in the
collodion process and had forced into the background the pyrogallic
acid developer, which had been suggested by Archer and was in general
use during the early fifties.

At the London World Exposition of 1862 instantaneous exposures
on collodion plates (ships, waves, clouds) were exhibited by English
(Breese, Wilson) and French photographers (Ferrier, Warnod) and
others, which attracted great attention.

“Wet collodion” dominated the photographic negative process from
the sixties to the eighties of the last century. The manipulation of the
process is by no means easy and requires a great deal of attention and
experience. It was used in particular by professional photographers to
the exclusion of all other methods in every branch of photography.

Chapter XLIII. beginning of photogra-
phy AS AN ART BY DAGUERREOTYPY, CALOTYPY,
AND THE WET COLLODION PROCESS

As early as the reports of the French commissions on daguerreotypy
in 1839, it was recognized that photography would have many useful
applications in the arts and sciences. Its astonishing fidelity in repro-
ducing natural forms and light and shade effects, together with the
delicacy of the earliest daguerreotypes, made such an overwhelming
impression on the celebrated painter Paul Delaroche that when leaving
Daguerre’s studio after a visit he exclaimed: “La peinture est morte
a partie de ce jour. 1 ” Delaroche, however, did not seem to have been
quite serious when expressing this rather exaggerated opinion, for
within the year he saw in Daguerre’s invention, not an enemy of paint-
ing, but “a great advantage for art.”

The great majority of artists, however, were of a different mind
and viewed daguerreotypy at first as a serious competitor of the fine
arts. But daguerreotypy was as yet far from justifying its entry among
the arts.

It was Le Gray, both photographer and painter, who expressed in
the fifties the following epigram: “La photographie est appelee a un
grand role dans le progres de l’art. Son resultat immediat sera de
detruire les inferiorites et d’elever les artistes de talent. 2 ”

The Scottish painter David Octavius Hill made calotypes, in 1843
to 1849, of single-figure portraits as studies for his paintings. His
conception of the composition, illumination, and treatment of the
subject, analogous to the instructions which painters give to their
models, is also quite the same as the viewpoint of modern artist pho-
tographers. Hill is considered the father of artistic photography. His
works, many of which are still extant in collections, especially in
Edinburgh, were gradually lost sight of, until they were again brought
to light in 1900. They then had all the interest of a new discovery. In
1901 seventeen new prints from the original negatives preserved in
Scotland were exhibited in the Royal Museum for Copperplate En-
graving at Dresden, together with pictures dating from the fifties. Dr.
Heinrich Schwarz, of the Modern Gallery, Vienna, brought (1929)
a hundred and eighty extremely interesting photographs by Hill from
Scotland to Vienna and staged an exhibit which fully sustained the
outstanding reputation of Hill’s work.

PHOTOGRAPHY AS AN ART

349

The catalog of the exhibition contains the following remarks on
Hill by Dr. Schwarz:

David Octavius Hill, born at Perth, 1802, died May 17, 1870, at Edin-
burgh, studied at the Edinburgh Academy under Wilson, painted at first
rural genre pictures and later turned to landscapes. He was a charter
member of the Scottish Academy (1838), of which he was secretary until
his death, and of the Scottish Art Union, the first society of its kind in
the United Kingdom. On the occasion of the founding of Scottish Free
Church (1843), Hill received a commission to commemorate the conven-
tion in a large painting containing four hundred and seventy individual
portraits. While engaged with this picture, which he did not finish until
1866, Sir David Brewster suggested to him the use of the calotype process,
recently invented and greatly improved by the English scientist Fox Tal-
bot. He studied the new process and made numerous photographs of his
models as an aid in portrait painting. In this way he photographed many
famous Scotsmen and Scotswomen of that day. He also produced many
landscapes and architectural photographs, all of them paper negatives by
Talbot’s calotype process. A technical aid, Robert Adamson, helped Hill
so that he might be able to concentrate his attention on his models.

F. C. Tilney’s The Principles of Photographic Pictorialism (1930)
contained a full-page portrait of Principal Haldane from a calotype by
Hill. The eighty full-page illustrations in this work showed the de-
velopment of artistic photography from the middle of the last century
to the present.

Another old master of the art of photography, equal to Hill in re-
pute, was brought to the attention of the Royal Photographic Society
at the session of December, 1922, by F. C. Tilney. This was Dr. John
Forbes White (1831-1904), who took up photography when twenty-
four years old; he was a pupil of the painters Reid, Chalmers, Israels,
Leighton, Millais, and others (Phot. Jour., 1923, p. 5).

Other English artists of note in photography during the years 1845
to 1 848 were Mayall, Reilander, and Robinson.

H. P. Robinson (1830-1891) is generally recognized as the founder
of the English School in pictorial photography. He used the wef col-
lodion process from 1854, cultivated landscape photography success-
fully about i860; he excelled chiefly in scenes with figures in the
foreground, by a special method of combination printing from several
negatives. He was an honorary member of the London Photographic
Society from 1871. Many of his pictures were published as inserts in
the journal of the society and other photographic periodicals. Of

PHOTOGRAPHY AS AN ART

35 °

course, Robinson’s genre pictures came to their full development only
when he made use of gelatine silver bromide plates, in the eighties.

The technique of Robinson’s pictorial composition, which found
many imitators, is suggested in an illustration which is reproduced in
the author’s Die Momentphotographie (2d ed., 1886), where Robin-
son’s method of combination printing is described in detail. For forty
years Robinson played a prominent role as an exponent and leader in
pictorial photography, and he enriched photographic literature by
several excellent publications. 3 Naturalistic Photography for Students
of the Art (London, 1889), by Dr. P. H. Emerson, also exercised a
great influence in this field.

The sculptor Adam Salomon, who later devoted himself to photo-
graphic portraiture in Paris, excited attention by his artistic concep-
tion of photography when he, in 1867, produced vivacious portraits,
properly lighted and with balanced background effects. 4 He also con-
tributed to publications on artistic photography.

In German technical literature, C. R. Wigand called attention in
1 856 to the artistic possibilities in photographic portraiture and recom-
mended to photographers the study of art. 5 British photographers
felt and considered themselves artists at the end of the nineteenth cen-
tury, as presented in the discussion by Alfred H. Wall on the relation
of photography to art, 8 while on the other hand many art critics like
B. F rank Howard opposed the claim of photography to be called an art.

The way for the introduction of the collodion process was smoothed
by its close connection with the improvement of photographic tech-
nique in artistic photography. The large portraits by Mrs. Julia
Margaret Cameron, exhibited at Paris in 1 867, although not at all sharp,
were of real artistic merit and were even then appreciated {Phot.
Archiv., 1867, p. 170); but it was not until many years later that they
received the general recognition and praise they deserved.

Of course, for this enumeration completeness is not claimed, since
numberless artistic photographs were made everywhere. Wide circles
of art-loving amateurs took up the most varied problems of artistic
photography after the introduction of gelatine silver bromide plates
and other important improvements in photographic technique and
applied photochemistry, because simplicity and ease of manipulation
played a very important part in the popularization of the art.

The credit for establishing photography as a business, with the
artistic viewpoint always in mind, is due incontestably to Disderi at

PHOTOGRAPHY AS AN ART

35 1

Paris. He also merits the distinction of having developed the technique
of photography, in particular that of professional portrait photo-
graphy.’

Andre Adolphe Eugene Disderi published, in 1853, his Manuel
operatoire de pbotographie, in which he described the technical side
of instantaneous photography. In 1855 he published a collection of
photographs reproducing objects exhibited in the Palais de l’Industrie
and the Palais des Beaux Arts. Disderi dealt with the artistic side of
photography in his Renseignements pbotographiques, 1855. In 1862
another book by him appeared, V Art de la pbotographie . 8 Disderi was
considered the outstanding portrait photographer of his time in Paris.
Napoleon III appointed him court photographer. In 1861 he instructed
French officers in photography under orders from the minister of
war. Disderi’s popularity is best shown by the fact that his character
was introduced in 1861 as a star attraction on the stage of a small
vaudeville theater in Paris by a realistic representation featuring his
bald head and tremendous beard.

VISITING CARD PORTRAITS (CARTES-DE-VISITE)

The first mention of the introduction of portraits the size of visiting
cards is found in La Lumiere, October 28, 1854, where it is stated:

E. Delessert and Count Aguado had an original idea for the use of small
portraits. Up to now visiting cards carried only the name, address, and
sometimes the title of the person whom they represented. Why could
not the portrait of a person be substituted for the name? This idea met
with great approval, since the special purpose of a visiting card could also
be expressed by the visiting card portrait. At ceremonial occasions the
visitor was to be photographed, wearing gloves, the head bowed as in
greeting, etc., as social etiquette requires; in inclement weather he was
to be shown with an umbrella under his arm; when taking leave a portrait
was furnished in traveling costume. From that time the term “carte-de-
visite” came into general use for portrait photographs of this small size.

According to another version, it was the Duke of Parma, an ancestor
of the Austrian ex-Empress Zita, who is to be regarded as the inventor
of visiting-card photography, because he had photographic prints
of his portrait pasted on his visiting cards instead of the printed name
in 1857. The first photographer who made these small-size portraits
is said to be Ferrier, in Nice, but they became fashionable only when
Disderi, as photographer to the court of Napoleon III, brought them

PHOTOGRAPHY AS AN ART

35 2

out. They were generally used in society at that time by persons who
exchanged these visiting-card portraits instead of their name cards
( Camera , 1922, I, 68).

This story, while rather interesting, is merely gossip and establishes
no priority in the invention of the visiting-card portrait. Their intro-
duction by Disderi greatly increased the popular demand for them
to the advantage of photographic studios everywhere in the world.

Disderi conducted this business on a grand scale, selling these cards,
not singly, but at first in lots of not less than fifty cards and later by
the dozen, at twenty to twenty-five francs per dozen. He attained
great popularity for himself and his product.

Dr. P. Ed. Liesegang 9 reports his visit to Disderi’s studio as follows:

At Disderi’s one finds truly a temple of photography, an establishment in
which luxury and elegance stand out in a class by themselves. His daily
output is figured at from three to four thousand francs. In the short time
of our visit he photographed eight persons. Disderi himself merely super-
vises the poses, etc. For our benefit he himself developed a negative
(eight visiting-card exposures on one plate) all extraordinarily successful.
He usually takes three to four persons on one plate, which he could easily
do, because there were always people waiting. The entrance on the Bou-
levard des Italiens is decorated with many photographs in gilt frames; one
mounts a stairway which is carpeted with red velvet and on its walls hang
paintings. On arriving at the top of the stairs, one is directed by a richly
dressed porter to the reception room, where three or four clerks are seat-
ed who enter the orders and receive the money. This room is furnished
in the style (a la boule) Louis XIV. In the waiting room are the finest
furnishings, but only one portrait, that of the emperor, in a gorgeous
gold frame, a mantel with a Venetian mirror, and albums of portraits of
high personages. The laboratory also is beautifully equipped; developing
is done over a large deep sink.

Disderi used in his later practice a multiple camera with four lenses
(1862) in order to make several exposures at the same time. For the
smallest sizes, postage-stamp size, a camera was used with twelve small
lenses; one of these cameras dates from about 1865 and was exhibited
at the time of the centenary celebration at Paris of the invention of
photography by Niepce.

CARTES-DE-VISITE IN VIENNA

Photographic cartes-de-visite were introduced in Vienna by Ludwig
Angerer in 1857. Ludwig Angerer, the son of a German Hungarian

PHOTOGRAPHY AS AN ART

353

forester, was bom August 15, 1827. He was a pharmacist and an
amateur photographer. His photographs made on a journey through
the Danube states in 1854 attracted general attention. Encouraged
by his success, he came to Vienna and opened in his residence a studio
of the first class, and he also made group pictures in the adjoining
beautiful garden. He also made large direct photographs by the
collodion process and was one of the first in Austria to develop the
artistic side of portrait photography. His studio was visited by the
most fastidious class of society. He died May 12, 1879. His brother,
Victor Angerer (1839-1894), was an officer in the engineer corps
and occasionally worked in his brother’s photographic studio. He
opened a portrait studio in Ischl (Austria) after the campaign of 1 859,
entered his brother’s firm as partner in 1873, and continued to conduct
the business along the lines of his brother’s ideas. We have already
reported on Ludwig Angerer’s work with the large Petzval lenses
(see Chapter XXXIV). The heirs of Ludwig and Victor Angerer
sold the property on which the photographic establishment stood
to Baron Nathaniel Rothschild, who erected his palace on it.

Victor Angerer, together with the photographer Dr. Szekely,
erected a dry-plate factory at Vienna in the early eighties. This was
for their own supply. The factory was closed up after a few years. He
built a new house for himself, with a studio, in 1892 and died there on
April 10, 1894. His son-in-law was the copperplate engraver
Blechinger, who achieved a great reputation as a portrait photographer
and landscape painter. His many services to photography were gen-
erally acknowledged. He published an extensive series of reproduc-
tions, among them all of the pictures of the painter Makart. Blechinger
and Leykauf were the founders of the publishing business for color-
heliogravure in Vienna.

Another well-known Austrian portrait photographer was Jagemann,
who had studios in both Vienna and Ischl, where the Emperor Franz
Josefs I had his summer residence. Jagemann, who died at the end of
1883, was the first official photographer appointed to the Imperial
Austrian Court.

Other later well-known court photographers of the wet collodion
period were Professor Fritz Luckhard, who made the best portraits
of the Emperor Francis Joseph and was secretary of the Vienna
Photographic Society and president of the Lower Austrian Trades
Society; then, Josef Lowy, who in addition to his portrait studio

PHOTOGRAPHY AS AN ART

354

conducted an establishment for reproductive processes (halftone,
gravure, and collotype) and was knighted; also, Charles Scolik, who
was one of the first professional photographers to experiment with
the production of gelatine silver bromide emulsions.

PHOTOGRAPHY FOR IDENTIFICATION PURPOSES

The first to propose the application of photography for the purpose
of identifying persons was Verneuil in 1853 (La Lumiere, 1853, p. 40).
He advised that travelers’ passports carry photographic portraits,
which could be produced with little trouble by the wet collodion
process and printed on silver chloride paper. Such portraits of identifi-
cation were used at the photographic exhibition in Berlin in 1865
on season tickets.

OTHER PHOTOGRAPHIC SIZES

In addition to visiting-card photographs, “cabinet size” portraits
were made in England about 1863 (Phot. Archiv, 1864, p. 26).
Windsor and Bridge, in London, advertised this popular size (Phot.
Archiv, 1866, p. 297). Photographs of the smallest size, in the form
of postage stamps, were brought on the market as early as 1863
(Phot. Archiv, 1863, p. 99). In the fifties photographic prints were
produced on silver chloride-starch paper with gilt borders, later ex-
clusively on albumen paper.

INTRODUCTION OF NEGATIVE RETOUCHING

In the early days of photography only positives were retouched or
colored, usually in a most inartistic manner. The invention of negative
retouching by the photographer Emil Rabending, in Vienna (i860),
was of great benefit to photography. Rabending, who died in Frank-
furt a. M. in 1886, was the first who regularly retouched the negatives
of his everyday output, but he avoided altogether retouching positives.
The retouching and coloring of photographs, always difficult to do
on albumen paper, became more and more difficult when the shiny
albumen print, with its purple-violet tone, became the style. Later
the albumen print was replaced by the modem emulsion, platinum,
pigment, and gum prints.

PORTRAIT GALLERIES IN THE MIDDLE OF THE
NINETEENTH CENTURY

At the time of the invention of daguerreotypy cameras were operated
mostly on light terraces or balconies out-of-doors, but when the

PHOTOGRAPHY AS AN ART

355

exposure was cut down by the use of fast lenses, the studio came into
vogue. They were usually located in painters’ or sculptors’ studios,
generally equipped with plate glass windows and, after the specializa-
tion for photography, with skylights (so-called pult-ateliers), which
were preferred; sometimes one found studios lighted by glass from
both sides and even so-called tunnel studios.

Further information on this subject can be found in Biihler’s Atelier
und Apparat des Photographen (1869) and “Atelier und Laboratorium
des Photographen,” supplement to Handbuch der Photographie ( 1 884,
I, 461 ) . The method of building portrait studios was first developed in
Paris; a very good survey of this subject is furnished by Captain
Henry Baden Pritchard’s work The Photographic Studios of Europe
(1882) of which a German edition was also published in 1882. Henry
Baden Pritchard was the editor of the Photographic News at that
time.

The portrait studio of Ch. Reutlinger in Paris, in which he worked
the wet collodion process is illustrated in the 1932 German edition
of this History (illus. 126). His specialty was the production and sale
of photographs of actors, artists, and other Parisian personages in
public life. It is typical in its northern exposure; the illustration
shows the equipment customary in the studios of the sixties and
seventies. A similar type of construction is Liesegang’s “Pulpit Studio,”
in Elberfeld, built in 1857 (see 1932 German edition of this History,
illus. 1 2 7 ) . In this studio Liesegang conducted a school of photography.

BLUE GLASS IN STUDIOS AND DURING EXPOSURES

Draper, in his first portrait photographs with daguerreotype plates,
used light blue glass (see note 4, Ch. xxxii) or liquid filters of a solution
of ammonium copper sulphate in order to tone down the glare of
sunlight on his models. The optically strong or visually bright rays
were softened by this method or excluded; but the “chemically active”
blue rays were not weakened very much. Guided by this idea, con-
firmed by Becquerel’s theory that the blue rays were the “activating”
rays, while the red ones were “antagonistic,” photographers in the
middle of the last century often used blue glass for their sky and side
lights. Beard, an Englishman, took out an English patent in June,
1 840, f or glazing photographic studios with blue glass. The F renchman
Disderi, in 1856, equipped his portrait studio with light blue glass
and stated correctly that dark blue glass absorbed three times as much
light in the collodion process. American photographers used blue

356 PHOTOGRAPHY AS AN ART

glass in their portrait galleries in 1862. The author remembers quite
definitely having seen, in Krems on the Danube (Lower Austria),
photographic galleries equipped with blue glass, which indicates how
generally it had been adopted.

Of course, the use of blue studio glass was dropped because the
lighting effects were later regulated by blue and other colored drap-
eries and because the necessity for a glaring illumination, blinding to
the eye, was no longer required in portraiture when the sensitivity
of photographic plates had been increased.

It is interesting to note that the cinema lighting technique of modern
times again introduced illuminating effects which are disagreeably
blinding to the eye. Moving picture artists may be guarded to a cer-
tain degree against suffering from the influence of the glaring lights
of electric arc lamps during exposures by inserting a blue glass filter
in front of the lights. This will permit the actinic rays to pass through,
while in the yellow and green zone of the spectrum to which the
retina is particularly sensitive, it possesses a strongly diminished trans-
mission capacity. George Jackel, of the Sendlinger optical glass works
in Berlin-Zehlendorf applied for a German patent of this phenomenon
based on “process for photographic exposures of persons with artificial
light,” dated March, 1926, which was granted September 6, 1928.
The author pointed out that owing to previous publications relating
to the use of identical blue glass filters this patent was not valid. 10
We must add that as early as 1851 Disderi used in his studio blue
muslin in order to soften the glare of the light, and in 1856 he employed
light blue glass panes.

The interior equipment of the studio was very simple in the be-
ginning of portrait photography, and it developed, with few excep-
tions, without the surplusage of the so-called artistic accessories of
later years. The introduction of painted backgrounds into photo-
graphic practice was discussed in The British Journal of Photography
of 1927 (p. 502). A book by G. T. Fischer, Photogenic Manipulation
(1845, p. 24), mentions that this was first used by A. J. F. Claudet, 11
who was born in France in 1796, became a partner of the firm of
Claudet and Houghton in 1834 at London, where he died in 1867.
Robert Hunt wrote, in 1853, advising against a white background.

Chapter XLIV. portable darkrooms; the-
ory AND PRACTICE OF THE WET COLLODION
PROCESS

The wet collodion plate had to be prepared immediately before
using and placed in the camera while still moist. 1 It was necessary to
develop it at once, and it usually was fixed immediately afterwards.
Both manipulations required water. For this reason the traveling
photographer needed a portable tent for a darkroom, or a wagon,
and in both, of course, space and weight were reduced to a minimum.

These accessories were described and illustrated in the “Atelier
und Laboratorium des Photographen,” supplement to my Handbuch
(1884, Vol. I). This reference contains illustrations of the apparatus
referred to in the section following.

Sometimes the tent was stretched over a framework and held to the
ground by pegs and ropes. An elastic opening permitted the passage
of the upper part of the operator’s body, as shown in Moignie’s tent
(Kreutzer, Zeitschrift fiir Phot., 1861, III, 158; Brit. Jour. Phot., VII,
177) . Often the tents were of very simple construction (see illustration
in Handbuch (1884, I, 519, or 1932, I, 495). A more elaborate form
was a box, equipped with silver baths, rinsing sinks, etc., screwed on
to the tripod used by Bourfield and Rouch (Kreutzer’s Zeitschr. fiir.
Phot., 1861, III, 142; Brit. Jour. Phot., VII, 275).

Smart’s tent, invented in 1858 and improved in i860, was very
roomy. Over a frame a tent of double black canvas was stretched; it
contained a work bench equipped with the necessary accessories.

Professional or commercial photographers, when engaged in out-
door work, employed two-wheeled hand-wagons on springs, easily
pushed (see Phot. Mitt., XVI, 316). Such photographic darkrooms
on wheels could still be seen in the streets of larger cities in the sixties
of the nineteenth century.

More ambitious photographers had substantial wagons built in such
large dimensions that, when required, one could mount the roof by
means of a small ladder in order to place the camera on it, so that the
public was not disturbed during exposures of street scenes.

In order to make it possible while traveling to produce a large
number of small pictures on a single plate in the camera, J. Duboscq
devised, in 1861, his “polyconograph,” a camera attachment containing
a row of five double plateholders, which were movable, so that fifteen

358 WET COLLODION PROCESS

exposures could be made on the one plate successively. Thence came
the idea of a plate magazine for dryplates, and Leon Vidal, in 1 86 1 ,
constructed his “autopolygraph,” a kind of a plate-changing holder,
which was improved (1882) by Marion of Paris.

The wet collodion process was ill-adapted for work with small
hand cameras, nevertheless much effort was made to overcome the
difficulties. We cite as an example the pistol camera, or “pistolgraph,” 2
invented and patented in i860 by Th. Skaife. It was constructed en-
tirely of brass, was only three inches long and one and one-half inches
wide. It was held in the hand like an ordinary pistol, and a trigger was
pressed to make the exposure. However, the traveling photographer
had to suffer the inconveniences of the wet collodion process and had
to carry around with him a miniature darkroom for collodionizing
with silver baths, etc. (Skaife, Instantaneous Photography . . . the
Manipulation of the Pistolgraph, Greenwich, i860). The work bag
employed with this pistolgraph was constructed of elastic, airtight
rubber cloth tubes, which could be inflated at will by means of a valve
affixed to one of the four corners, where the tubes were fastened to
the wooden base. The inflated bag was nine to ten inches high; the
flat floor was about twelve inches square. In front was a circular opening
covered by a tight-fitting flap, which was entirely closed during the
manipulation.

From these simple beginnings developed later the many different
devices for changing or developing dryplates without a darkroom.

The introduction of “instantaneous” photography was hastened
by difficulties of the wet collodion process. Skaife, in the pamphlet
mentioned, Instantaneous Photography (i860), states very appro-
priately: “Speaking in general, instantaneous photography is as elastic
a term as the expression ‘long and short.’ ”

Landscape photography, particularly alpine photography, in the
fifties and sixties, involved very troublesome and daring expeditions,
as the cameras, tents and darkrooms had to be hauled up high moun-
tains. According to E. Stenger in “High Mountain Photography in
the Last Century” ( Camera , 1930, p. 8), Aime Civiale was probably
the first who, in 1857-1858 and later, photographed the Pyrenees and
made large composite panoramas. He made exposures from Piz Lan-
quard (3,266 meters-10,715 feet), which he exhibited at the Academy
of Science in Paris. Notwithstanding all the efforts made to simplify
his equipment, the total weight reached about 250 kg. (551 lbs.) and

WET COLLODION PROCESS

359

required twenty-five men and mules for its transportation. This
achievement was far excelled by the French photographer August
Bisson, who made photographs on the summit of Mont Blanc in 1 86 1
under the greatest difficulties and was acclaimed a hero and a con-
queror. He also required twenty-five carriers and guides.

Members of the Austrian Alpine Society arranged a photographic
expedition to the Grossglockner in July, 1863, under the guidance of
Jagermaier, the photographer, and Adolf Obermiillner, landscape
painter. This photographic glacier expedition was celebrated as haz-
ardous and especially glorious, and the satisfactory results obtained
were highly praised. Eighty-four 14 X 17 inch negatives of alpine
views were made. Later photographs of the Alps were made by
Wiirthle of Salzburg. The photographer of today, working with a
small hand camera and producing large prints from his small negatives
without trouble, has no conception of the difficulties involved in these
early expeditions. The difficulties encountered in military photography
in the wars during the collodion period seem incredible today.

The first official war photographer was Roger Fenton, secretary of
the Photographic Society of London, who was sent by the English
government to make photographs of the Crimean battlefields in 1855.
He traveled in a closed wagon, which also served as his darkroom.
An album containing forty-nine silver prints of his war photographs
now forms part of the historical collection of the Royal Photographic
Society. Fenton also made numerous negatives for Paul Pretsch’s helio-
graphic reproductions.

The American photographer Matthew B. Brady was the next, who
during the Civil War of 1861 to 1865 made thousands of photographs
of war scenes; his pictures of the battle of Antietam, in Maryland,
excited much attention at the time. Photographic exposures from
balloons were also attempted, but with little success.

Photography for military purposes was introduced in the curriculum
of the Royal Military Academy at Woolwich, England, by John
Spiller in September, 1857 (Phot. Archiv., 1861, p. 267; 1862, p. 88;
and 1864, pp. 59, 134; Phot. Mitt., 1864, p. 161).

FURTHER INVESTIGATIONS OF THE WET COLLODION PROCESS

The experience of the photochemical process gained in daguerreo-
typy was not easily adaptable for use in the collodion process, because
this new method was quite different from the earlier one; it was, how-

360 WET COLLODION PROCESS

ever, of great assistance in its development. Many books on the wet
collodion process were published. One of the best of these was written
by the English chemist T. Frederick Hardwich. It was particularly
valuable because he treated photochemistry exhaustively and gave an
original and very useful method for the production of photographic
collodion cotton, in which he emphasized the definite advantage of a
strong excess of sulphuric acid in the nitric mixture. He was a teacher
of photography at King’s College, London, when he wrote, in the
fifties, his Manual of Photographic Chemistry, Including the Practice
of the Collodion Process. The first and second editions were published
in 1855; sixth edition, 1861, which was also translated into German
( 1 86 3 ) . He resigned from his position as teacher and became a preacher
in one of the mining districts, where he was active until the middle of
the sixties . 3

Of the early books on the wet collodion process we mention Le
Gray, Photographie (1850, 1852, 1854); Barreswil and Davanne,
Chiinie photographique (1854, 1858, 1864); Belloc, Traite . . . de
la photographie sur collodion (1854); Belloc, Les Quatre Branches
de la photographie (1855, 1858); Belloc, Photographie rationelle
(1862); Bingham, Instruction in the Art of Photography (1855);
Blanquart-Evrard, La Photographie, ses origines, ses progres . . .
(1869); Disderi, Manuel operatoire de photographie sur collodion
( 1854) ; Disderi, L' Art de la photographie (1862); Martin, Handbuch
der Photographie (1851, 1857, 1865); Chevalier, Photographie sur
papier sec, collodion . . . (1857); Legros, Encyclopedic de la Photo-
graphie (1856); Liesegang, Handbuch der Photographie auf Kollo-
dion ( 3 ded., 1861); Liesegang, Verfahrenzur AnfertigungvonPhoto-
graphien, Ambratypen und Sanotypen (1859, i860, 1861, and other
years). See the Handbuch (1927, 11(2), 43) for other references.

PHOTOCHEMICAL OBSERVATION ON THE COLLODION PROCESS

Experimenters concerned themselves with the question whether
the wet silver iodide collodion plate retains the latent image unchanged
or whether it soon fades away as in daguerreotype plates. Latent light
images on silver iodide collodion with excess of nitrate of silver, when
stored away, do not fade, as Reissig was the first to observe {Phot.
Korr., 1866, p. 124; and 1867, p. 53). (In contrast to daguerreotype
plates see Chapter XXXI). On the other hand, bathed collodion dry
plates which liberate silver nitrate in washing and were preserved

WET COLLODION PROCESS 361

with tannin, were subject to the deterioration of the latent image after
a few months. Silver bromide collodion plates also do not retain the
image, while silver bromide gelatine plates, as is well known, keep the
latent image unchanged for a long time.

In applied photography with wet collodion the iodides were the only
salts used. Soon it was discovered that in this process also, as in daguer-
reotypy, the iodine-bromide compound added great advantages in
the matter of sensitivity and rendering of the middle tones of the image.
Who first employed bromides in collodion became a burning question
when Tomlinson, who had bought rights for the use and application of
Cutting and Turner’s (1854) United States patent covering the use
of bromides in the production of photographic collodion, demanded
fifty to two hundred dollars from every photographer and tried to
enforce his demand with the aid of the courts. Since Cutting insisted
that he had made his invention in the spring of 1852, it became im-
portant to prove that bromides had been used in photographic col-
lodion before that year (Phot. Archiv., i860, p. 189; 1866, pp. 337,
396) . This proof was adduced. In the second edition of Chimie photo-
graphique, by Barreswil and Davanne (Paris, 1851), the following
statements are printed: “Some photographers added to their collodion
bromine salts (cadmium, ammonium, or potassium-bromide) . . . Sil-
ver bromide reproduces the green better . . . The quantity is usually
four parts iodide, one part bromide.”

These statements of the Parisian scientists set the standard for later
years, and the relation of bromides to iodides was generally observed
in the proportions of 1 to 3-6; pure iodide collodion being used only
for the slow-acting collodion of reproductive processes ( Handbuch ,
1927, Vol. II, Part 2).

Pure bromide collodions were not deemed advantageous for the
photographic technique of the times; only when emulsion photography
was introduced did their use follow.

The greatest improvement in the preparation of photographic col-
lodion was the introduction of the use of iodide and bromide. At first
iodide and bromide of potassium, as well as ammonium salts, were
tried, but they were less permanent. An important step was the intro-
duction of cadmium salts in preparing negative collodion by Laborde
in 1853, especially in mixtures of alkaline iodides, by which lasting
and sensitive collodions were obtained, and it was recognized empiri-

WET COLLODION PROCESS

362

cally that cadmium and alkaline iodide (or bromide) had a favorable
affinity for each other.

This mixture forms double salts. The chemical composition and
the properties of cadmium double salts (complex compounds) of
cadmium iodide and bromide with the alkaline salts were investigated
by the author (Phot. Korr., 1876, p. 92). He found new cadmium
double salts which furnished a maximum of permanency and sensi-
tivity. He was still a student at the Vienna Polytechnikum when he
produced these double salts of cadmium; they found their way into
practice when negative collodions prepared on this basis were used
first in portrait photography and, later, in the halftone process. In the
literature on the subject this collodion is designated as “Reproduction
Collodion of the Graphische Lehr- und Versuchsanstalt,” because
the author introduced it there as “halftone collodion,” but it is iden-
tical with his double-salt collodion of 1876. These double salts for
negative collodion received a bronze medal at the Paris Exposition, in
1878, and the silver Voigtlander medal from the Vienna Photographic
Society. Proprietors of large establishments in Vienna, such as Ger-
tinger, Dr. Szekely, and others, used this collodion for portraits, and
Max Jaffe employed it in his collotype works.

MANIPULATION OF COLLODION PLATES

Iodized collodion was poured on the glass plates, and when the
coating became firm, they were dipped in a strong silver-nitrate bath
and exposed while still moist. In the very beginning iron sulphate,
which had been recommended by Hunt for paper, was used as a de-
veloper. Archer, who was an orthodox calotypist, stuck to pyrogallic
acid for developing (1851), but after a while he turned, like all other
photographers, to iron sulphate developer, which permitted the
shortening of the time of exposure. Archer already recognized the
possibility of intensifying the collodion negatives before fixing with a
developer of silver nitrate, or of developing further (1851). Archer
was also the inventor of a collodion stripping film by coating with rub-
ber (Phot. Jour., 1855, II, pp. 262, 266); these were probably the first
transparent photographic film negatives.

FIXATION OF WET COLLODION PLATES

The fixation of wet collodion plates was done at first entirely with
sodium hyposulphite. It was not until 1853 that M. Gaudin published

WET COLLODION PROCESS

363

the use of potassium cyanide, which acts more rapidly and contributes
to clearing up of the negative. It is still used today, especially with
halftone negatives.

INTENSIFICATION

Herschel was the first to announce the bleaching of silver images
with mercury chloride under formation of mercurous chloride. The
formation of this white precipitate on the collodion negative was
applied as an intensifier by the first pioneers of the collodion process,
in particular by Archer (1851). According to Horn’s Phot. Jour.
(1854, I, 91), credit is due to the Frenchman Lespiault for the inven-
tion of intensifying by blackening of the white precipitate with am-
monia. The blackening of negatives bleached with chloride of mercury
by hypo was reported by Archer as well as by Le Gray (1854); the
yellowish-brown coloring with iodide of potassium was reported by
Maxwell Lyte (1853); and intensification with uranium nitrate and
potassium ferricyanide by Selle in 1865 ( Handbuch , 1927, Vol. II,
Part 2).

The mordant dye action of murexid 4 on the negative, bleached with
chloride is reported by Carey Lea (1865), and he invented the first
mordant dye picture.

A splendid intensifier of line negatives was that with copper chloride
(bromide) and silver nitrate, suggested by Abney in 1877, which has
since been largely employed by photoengravers (Eder, Die Photo-
graphic mit Kollo diumverjahren ) .

LEAD INTENSIFICATION AND INVENTION OF DARKENING OF SILVER
WITH FERRICYANIDES

The methods of intensification based on the reaction of ferricyanide
on silver have a far-reaching importance in applied photography. The
first and earliest application of a mixture of potassium ferricyanide
with uranium nitrate for intensifying and brown coloring of collodion
negatives was made by Selle in 1865 {Phot. Archiv, 1865, pp. 326,
393). This method met with little approval, and the progress of the
chemical reaction on which this intensifying process is based was not
investigated. In 1875 the author, together with Captain Victor Toth,
found that mixtures of potassium ferricyanide with lead salts deposit
a precipitate of silver ferrocyanide and lead ferrocyanide. This caused
a strong intensification, which, while giving a white color, could be

364 WET COLLODION PROCESS

made by suitable reactions inactinic and protective. This was reported
by them in a treatise, Die Bleiverstarkung, eine neue Verstarkungs-
methode, to the Vienna Photographic Society on December 14, 1875
(Phot. Korr., 1876, p. 10).

The bleached negatives were blackened with dilute ammonium sul-
phide. This was the strongest intensifier known at the time. It was
also reported that Schlippe’s salt (sodium sulphantimonate) darkened
the negative “to a nice reddish brown” and intensified it. Eder and
Toth mentioned that “silver reduced the potassium ferricyanide, which
changed to ferrocyanide of potassium,” and that it formed with the
lead salt an insoluble compound (ferrocyanide of lead).

The author 5 investigated the exact chemical theory of reaction by
this group of ferricyanides on silver. The chemical equations were
published and demonstrated by chemical analysis in his dissertation:
“Die Reaktion von rotem Blutlaugensalz auf metallisches Silber,” in
the Phot. Korr. (1876, pp. 26, 172), as well as in the /our. f. prakt.
Chemie (1876). The author also stated that the same scheme operates
in the darkening of silver images with uranium salts (reddish brown
color) . He concluded that “a mixture of ferricyanide and ferric oxide
salts (ferrisulphate) behaved similarly; giving a beautiful blue pre-
cipitate, or prussian blue, which colored the negative a strong and
distinct blue.” This was the first description of blue toning, and thus
was determined the chemical basis for coloring and intensifying meth-
ods.

A later dissertation by Eder and Toth, entitled “Neue Unter-
suchungen fiber die Bleiverstarkung,” was presented at the session of
October 1 7, 1 876, of the Photographic Society of Vienna (Phot. Korr.,
1876, XIII, 207, 221). At this time it is described also how white
silver images intensified with lead could be turned yellow by a solu-
tion of potassium chromate (formation of chrome yellow) and how
they could be colored brown by permanganate. On page 222 of that
essay it is mentioned that such yellow silver images could be colored
a beautiful green by pouring on them a solution of iron chloride
(super imposition of chrome yellow and prussian blue); also, that the
white ferrocyanide image turns reddish brown under uranium salts,
but red under copper chloride copper ferrocyanide. It is also expressly
emphasized that the basis of this photographic coloring method need
not always be a lead precipitate.

In the footnote (Phot. Korr., 1876, XIII, 223) it is stated: “The

WET COLLODION PROCESS 365

action of metal chlorides on pure ferrocyanide of silver is quite similar;
silver chloride and corresponding metal ferrocyanides form; thus iron
chloride will color the image blue, copper chloride will color reddish-
brown, etc.” Coloring with cobalt and nickel salts is also referred to
there. These statements all related, first of all, to collodion plates, and
a large collection of these blue, yellow, green, and reddish-brown
diapositives were exhibited in the Photographic Exhibition at Vienna
in 1885. Today we need to consider chiefly silver images on gelatine
emulsion, but in the author’s Die Pbotographie mit Bromsilbergelatine-
Emulsion (2d ed., 1883, p. 176), it is clearly stated that these ferri-
cyanide methods are also applicable to gelatine silver bromide images.
This publication made public the application of the methods of color-
ing and intensifying for the whole field of photography, comprising
toning in blue, green, yellow, orange, and brown with lead, copper,
uranium, chromium, nickel, and cobalt salts. The outline of the his-
torical development of this research must be taken into consideration
in any evaluation of priority claims from other sides. For instance,
one of the elements of numerous modern three-color methods consists
in the production of diapositives or paper prints, which are colored
with chrome yellow or with prussian blue according to the ferricyanide
method. It must be pointed out, also, that the modern methods of
bromoil printing with potassium ferricyanide, as well as the koda-
chrome process and certain mordant dye toners, are all to be traced to
the author’s chemical formulas of the reaction of ferricyanide on
silver, as can be fully understood when the secondary formation,
determined by him, of potassium ferrocyanide and the reduction from
chromic acid to chromic oxide as the decisive agent in the tanning of
the gelatine are recognized (Phot, lnd., 1925^. 1355).

Victor Toth, born 1846, in Hungary, was the son of an army
surgeon. He studied at a military school, entered the army as officer
of engineers, and was transferred to Krems on the Danube (Lower
Austria) in 1870. In the same regiment served another officer, Guiseppe
Pizzighelli, and both engaged in amateur photography with the wet
collodion process, using Busch combination lenses for portraits and
landscapes. They sought advice at the Military Geographical Insti-
tute and from Professor Emil Hornig, who later became president
of the Vienna Photographic Society. Toth resigned from the army
and in 1873 became attached to the general inspection service of the
Austrian railroads. He equipped a private laboratory, where he con-

366 WET COLLODION PROCESS

tinued his experiments and, in collaboration with the author, worked
out the lead intensifier. About the discovery of the pyrocatechin
developer by Eder and Toth see Chapter LIX. Toth died in Hungary,
in 1898.

In modem times R. Namias, in Milan, used lead intensification for
producing mordant dye pictures. He converted silver images into lead
images with the Eder-Toth lead intensifier and colored them yellow
with chromates (chrome yellow); he converted them with sodium
sulphate into lead sulphate, in which class fall directly various dyes
(auranium saffranin, methylene blue, etc.); or he converted the lead
image with alkali into lead oxide. In this manner he produced mordant
dye pictures in various colors (Brit. Jour. Phot., Color Supplement,
September, 1909).

The reaction, mentioned above, of chemically pure potassium
ferricyanide on the fine grained metallic silver process under the
formation of ferrocyanide of silver, which is soluble in hypo (Farmer’s
reducer is based on this) . Lead intensifies retained their place in photo-
graphic reproduction methods in the earlier wet collodion process
and the modern halftone process with collodion emulsion (Handbuch,
1927, 11(2), 121, “Photography mit Kollodiumverfahren”).

ACTION OF THE SOLAR SPECTRUM ON COLLODION PLATES

Heinrich Jacob Muller was the first to photograph the solar spectrum
on wet collodion plates, in 1856, together with Fraunhofer’s lines
(Poggend. Annal., XCVII, 135). Muller, born in Cassel (Germany)
in 1 809, was a teacher of physics in Giessen and in 1 844 professor of
physics at the university. He is widely known for his publication
in German of Pouillet-Miiller’s T extbook on Physics; the first edition
appeared in 1856-1857, and there were many later editions.

Helmholtz also photographed the solar spectrum in 1857. Ruther-
ford and Seely, in New York, produced a spectrum in fifteen sections,
two meters (6 9/16 feet) long. 6 William Crookes used in his investi-
gations on the photography of the solar spectrum (1855-1856) a
quartz lens with two quartz prisms, and J. Muller also worked with
quartz prisms (Poggend. Annal., XCVII, 616). The astronomer Wil-
liam Huggins photographed the spectrum of stars with a prism of Ice-
land (calcareous) spar and two quartz lenses (Handbuch, 1884, 1,41).

J. Muller recognized wet silver iodide collodion plates as sen-
sitive from the blue violet next to the Fraunhofer line G up to line Q

WET COLLODION PROCESS 367

in the ultraviolet. Eisenlohr found a similar result with a difraction
spectrum. According to Becquerel the action begins in the blue violet at
G/3 H, which later scientists elaborated and in a general way con-
firmed. All early scholars (Becquerel, Crookes, Schultz-Sellack, and
others) found that silver bromide as used in the wet collodion process,
with pyrogallic as well as with iron vitriol developer, is sensitive to the
light blue and into the green and beyond (analogous to daguerreo-
type plates). Iodo-bromide of silver shows increased sensitivity in the
wet collodion process towards the bluish green, in which it is similar
to pure silver bromide. The most comprehensive investigations on the
behavior of silver bromide, in the form of wet collodion plates, towards
colored light are those of Crookes (1855). During his experiments in
photography of the solar spectrum be observed a deeper action towards
the green of the spectrum in silver bromide than in silver iodide. He
examined the ability of a wet silver bromide plate, with iron vitriol
development, to reproduce the color-tone values of variegated leaves
of flowers and found the result more pronounced than when silver
iodide was employed. Crookes improved the results he obtained by
inserting a light filter of quinine sulphate in front of the lens, which
absorbed the ultraviolet and part of the violet. In these experiments
Crookes became the pioneer in the application of suitable light filters
and the use of silver bromide in the photography of colored objects;
he utilized spectrum photography as an alternate control with the
photographic behavior in the photography of colored objects in nature
(Horn’s Phot. Jour., 1855, p. 28).

SOLARIZATION, REVERSAL INTO POSITIVES

The wet collodion plate (silver iodide with silver nitrate bath)
solarized under long exposure from the indigo to the violet of the solar
spectrum, which Crookes had already recognized.

Seventy years ago Sabattier 7 observed the phenomenon of reversal,
i. e., the changing of a negative image on the wet collodion plate to
a positive during the development when suddenly daylight shone on
it (pseudo-solarization) ; lights changed into shadows, and after scarce-
ly a minute it turned into a complete positive. Such positives by re-
versal Sabattier exhibited, in September and October, i860, before
the French Photographic Society in Paris (Bull. Soc. frang. phot., 1 860,
pp. 285, 306, 3 12, also July, 1862; Horn’s Phot. Jour., XVIII, 50; XIX,
37). De la Blanchere, Rutherford, and Seely made the same observa-

WET COLLODION PROCESS

368

dons. This Sabatder reversal phenomenon also played a part in photog-
raphy with gelatine silver bromide, which Liippo Cramer describes
exhaustively in his “Grundlagen der phot. Negativverfahren” (in
Handbuch, 1927, II ( 1 ) , 623).

PICTURES CAPABLE OF DEVELOPMENT BY MECHANICAL PRINTING

The possibility of obtaining developable photographic images on
silver iodide layers by mechanical printing was observed by Carey Lea
(Silliman’s American Journal of Science , 1 866, Ser. 2, XLII, 198; Phot.
Archiv., 1 866, p. hi); later, by Aime Girard with collodion, tannin
or albumen dry plates (Bull. Soc. frang. phot., 1866, p. 88). Warnerke
made detailed reports on gelatine dry plates (Phot. Archiv., 1881, p.
120), which resulted later in further investigations by others and be-
came of value in the film industry (Handbuch 1885, II, 18; 1890,
111 , 94 ).

DEVELOPMENT OF THE LATENT LIGHT IMAGE AFTER FIXATION

Y. Young was the first to make, in 1858, the theoretically impor-
tant discovery that the latent photographic image on collodion dry
plates (Taupenot plates) could be developed after fixation with physi-
cal developers, 8 and he reported it to the session of the Manchester
Photographic Society, January 5, 1859 (Brit. Jour. Phot., 1859, p. 20),
describing it as “developing after fixing with cyanide.” He found that
the exposed plate could be developed after fixing, either at once or
after a few days, with pyrogallol and silver nitrate, which was con-
firmed by numerous other scientists, such as Davanne and Bayard, in
1859. This phenomenon may also be easily observed in silver bromide
gelatine films. In the World W ar the Secret Service seized photographs
treated after this manner. On the fixed silver-bromide-paper pictures
(silver bromide post cards) latent invisible letters were written in the
white part of the sky, 9 which kept their properties a long time even
in light and could not be made visible by any kind of chemical media,
with exception of physical development, such as acid metol with silver
nitrate.

RESOLVING POWER OF WET COLLODION PLATES

Wet collodion plates showed great capacity for resolving the fine
details of the picture in a sharply ascending blackening curve with
great clearness, which has kept for them a special usefulness until

DIRECT COLLODION POSITIVES 369

modern times in the photomechanical processes. They had to give
way with respect to sensitivity, in the reproduction of middle tones, to
greater durability, and especially to the color sensitiveness in other
photographic films in which, as Herschel prophesied, silver bromide
played a dominant part.

Chapter XLV. direct collodion positives

IN THE CAMERA

The production of direct positive images in the camera became a
technical speciality of the collodion process. This was not a matter of
employing any of those new photographic processes described in
Chapter XXXIX, but dealt with ordinary negatives with white silver
precipitate which were made very weak (light) with a solid black
background that appeared under reflected light as positive images.
This process was used at the time when the daguerreotype was already
on the wane and led to ferrotypes and to pannotypes.

The starting point of all these methods is the observation that glass
negatives made by the albumen or collodion process and developed
will appear negative when looked through against the light, but posi-
tive when looked at against a dark background.

The originator of ferrotypes, which were produced on black lac-
quered tinned iron by the wet collodion process, was the Frenchman
Adolphe Alexandre Martin (1824-1896), the only pupil of Leon
Foucault; he was a college professor in Paris and interested himself in
photography. In 1852 and 1853 he presented to the Societe d’En-
couragement and to the French Academy of Sciences two memoirs,
in which he described a process for the production of direct positives:
(a) on glass, the back of which was made opaque, and ( b ) on tinned
iron, which was the starting point of ferrotypes and pannotypes.
Martin’s experiments to produce direct positives on glass are described
in La Lumiere (1852, pp. 99, 1 14), and on metal, in the same publica-
tion (1853, p. 70). Wallon, in his speech commemorating Martin’s
death, at the session of the French Society of Photography, December
4, 1896, confirmed the above statements, and at this session Martin’s
sons presented two early specimens of the process to the society (Bull.
Soc. franp. de phot., 1896, pp. 314, 577).

DIRECT COLLODION POSITIVES

370

Adolphe Martin also made experiments in the production of gun-
cotton for photographic purposes. He took part personally in the con-
struction of the large instruments for the Paris Observatory and con-
structed a reflection mirror of greater dimensions than had been
achieved before that time. He published his procedure for silver plating
of mirror surfaces with invert sugar and silver nitrate. He also in-
terested himself in the calculation of photographic lenses and published
his method in the Bull. Soc. frang. de phot, for 1892 and 1893.

Similar positive collodion images on black waxed linen were pre-
sented for the first time to the French Academy of Sciences by the
firm of Wulff & Co., in 1853, which called them pannotypes (from
the Latin pannus = cloth) ; the process was widely sold for one
hundred francs. Pannotypes soon became generally known, and many
professional photographers made commercial use of them, but they
were displaced in studios and by itinerant photographers between 1859
and 1863 by ferrotypes and albumen prints. Very few specimens of
pannotypes have been preserved, owing to the fragility of the black
waxed linen which served as a base for the picture image.

In the production of direct positives in the camera the black lac-
quered galvanized iron or tinned plate gradually displaced all other
materials. At first these collodion positives on black backgrounds were
called “melainotypes .” 1 They were very popular at the end of the
fifties or at the beginning of the sixties and were commonly called
“tintypes” or by the name which later became generally used, “ferro-
types .” 2

The black lacquered tinned plate had the advantage over other
materials of being stiff and unbreakable and therefore easier to handle;
it was easily cut up and could be easily fitted into brooches, lockets,
and so forth.

Professor Hamilton L. Smith was the first to make ferrotypes in the
United States, and he and Griswold, of Peekskill, New York, intro-
duced them into the photographic industry.

Smith took out a patent for his processes, in which he specifies that
he coated his tinned plate with a boiled mixture of asphaltum, linseed
oil, and umber or lampblack; and on top of this the collodion image
was exposed.

Peter Neff bought Smith’s patent in 1857 and manufactured the plates
until 1863. Griswold started to make them in the same year and sold
them to the trade as “ferrotype plates.” They were used by itinerant

CHEMICAL SENSITIZERS

37i

photographers in Europe under the name “American instantaneous
photography” ( Handbuch , 1927, Vol. II, Part 2).

Later, around 1900, “dry” ferrotypes were introduced in the form of
gelatine silver bromide plates and a special apparatus, so-called photo-
graphic automats were used, in which illumination (magnesium flash-
light or electric light) development and fixation were operated auto-
matically. These automats were used at expositions and fairs, but the
results were of mediocre quality. Silver bromide prints displaced the
ferrotypes even for the rapid process demanded for these incidental
photographs..

Chapter XLVI. chemical sensitizers for

SILVER HALIDES

It must be mentioned briefly that Poitevin stated in 1863 1 that silver
iodide formed with an excess of potassium, which is almost completely
insensitive, becomes light-sensitive with tannin, gallic acid, or ferrous
sulphate, just like silver nitrate. He attributed this to the reducing
property of these sensitizers, while, on the other hand, H. W. Vogel
recognized, correctly, that the action of the “chemical sensitizers” for
halide combinations of silver salts (silver iodide, bromide, chloride)
rests, in the first place, on their ability to combine iodine, bromine, or
chlorine (acceptors of iodine, and so forth).

This theory of Vogel and its consequences for photographic practice
became authoritative in the later development qf photographic history
and was supplemented by Vogel’s discovery of “optical sensitizers.”

Poitevin also presented a new dry-plate process. He washed col-
lodion plates (silver iodide, dipped in silver-nitrate bath), and made
them insensitive by immersing them in an excess potassium iodide
solution. He again washed and sensitized them immediately before
exposure by flowing over them a 5 per cent solution of gallic acid. He
exposed and then developed them with iron sulphate under addition
of silver nitrate. While this method achieved no practical use, it must
be designated the precursor of the similar method of Russel (tannin
dry plates).

Chapter XL VII. THE DRY COLLODION PROC-
ESS AND THE INVENTION OF ALKALINE DE-
VELOPMENT

After all that has been said, one can readily understand the desire
of all photographers, especially when traveling, to have a dry process
introduced in place of the wet method.

The pure albumen plate of Niepce de Saint- Victor could, it is true, be
used dry, but it was exceedingly slow. Therefore all hope centered in
the collodion plate, which, however, showed great sensitivity only
in the wet state.

Since the silvered collodion-bath plate cannot be dried with the bath
silver adhering to it, owing to corrosion of the coating, which is eaten
away by the formation of silver crystals, and since it loses its sensitivity
almost completely after washing it in water and drying, there began a
search for “preservatives” which would retain sensitivity in the dry
collodion film.

But all these experiments led to no lasting practical success. The
Frenchman Taupenot succeeded in making the first real progress by
inventing a combination of silver iodide collodion film, which he coated
with albumen. Taupenot (1824-1856) was professor of chemistry and
physics in the Prytanee Military Academy at La Fleche (Dept, of
Sarthe) .

At first the silver iodide film of the wet collodion plate was coated
with honey in order to keep it moist and sensitive, which succeeded up
to a certain degree. This was first suggested by Maxwell Lyte, on
June 17, 1854, in Notes and Queries.

Maxwell Lyte, an amateur, deserves a great deal of credit for his
activity in the development of photography. A biography of him may
be found in the British Journal of Photography (1906, p. 206). His
honey collodion process was one of the earliest phases of the dry col-
lodion process. Lyte was a chemical engineer and one of the first to call
attention to the danger that “antichlore” (hypo) in photographic
mounts threatened the durability of silver images. He wrote many
articles on photographic processes, for instance, on the intensification
of negatives with mercury chloride and ammonium sulphide.

George Shadboldt preceded him by a few days in recommending
honey as a preservative to the London Photographic Society, on June
6, 1854. But this method of preservation for collodion plates was un-

DRY COLLODION PROCESS

373

satisfactory, because the demand was for permanently dry collodion
plates. Robiquet and Duboscq ( 1855), then the Abbe Desprats (1856),
sought to accomplish this by addition of resin.

Taupenot’s process consisted of washing the collodion film after it
had been sensitized in a silver nitrate bath, coating it with albumen
and drying it. The plates were once more dipped in the silver bath and
dried again; they lasted for several weeks.

T aupenot published his collodio-albumen process at the end of 1 85 5 1
and exhibited the first specimens of his work, which attracted atten-
tion and admiration on account of the fine quality of the image ob-
tained; other examples of his process were exhibited at the London
Exposition of 1 862 as objects of interest.

Taupenot’s process met with immediate favor as early as 1855; it
placed in the hands of experienced photographers a practical method
for obtaining good results and simplified outdoor photography, al-
though, of course, it was necessary to give longer exposures than with
wet collodion plates (often several minutes) . For instance, the French-
man A. Ferrier made a notable series of views of the Swiss lakes in 1857.
In England, J. Mudd, J. Sidebotham, and others worked this collodio-
albumen dry process with great success (1860-1870).

While Taupenot’s process was largely used from the end of the
fifties to the early sixties for landscape photography, it did not seriously
interfere with the general use of the wet collodion process, but con-
tinued in favor for many years in conjunction with photomicrography.
We cannot give all the various modifications of this process which
have been published ( Handbuch , 1927, Vol. II, Part 2).

In Germany the Desprats resin method of 1856 was employed at
first. One of the first photographers to occupy himself with the pro-
duction of iodine-bromide collodion bathed dry plates with high silver
bromide content and the addition of resin (gum), who as early as 1856
produced beautiful landscape photographs (with pyrogallic acid silver
nitrate developer), was Hermann Krone 1827-1916). 2 Later, Krone
turned to Taupenot’s albumen process and its modifications.

Richard Hill Norris, in England, was probably the first to recog-
nize the advantage of using a coating of gelatine or gum arabic as a
preservative for collodion dry plate. He patented his process September
1, 1856 (No. 2,029). He sensitized the iodized collodion with silver in
the usual manner; this he then dipped in an aqueous solution of gelatine,
gum, or some other viscous vegetable substance in order to keep the

DRY COLLODION PROCESS

374

pores of the collodion film open while drying and to keep the coating
sensitive. He also recognized the fact that after coating with gelatine
the collodion film could be stripped off the glass.

The Norris process is worthy of attention not only for its clear
recognition of the value of gelatine and the role it plays in preserving
the structure of the collodion film but also because this process was
the beginning of the manufacture of photographic dry plates. V. von
Lang, the official Austrian observer at the London World Exposition,
in 1862, who later became professor at the University of Vienna,
reports: “The dry plates, ready for use, manufactured by Norris are
being sold in all the larger towns of England and are said to give
good results.” 3

The collodio-albumen process was displaced by the tannin method
of Major C. Russell (1861), because it was simpler and more certain
in manipulation, and because the development brought out the image
more rapidly and strongly. The sensitized collodion film was thor-
oughly washed in this process and, while still moist, flowed with a
tannin solution, and then dried. 4 Beautiful specimens of this process
were exhibited at the London World Exposition in 1862.

How difficult it was, with the means at hand at that time, to produce
a dry plate which would be practical and satisfactory is shown by a
competition organized by the Marseilles Photographic Society in
1862, in which a prize of five hundred francs was offered for a dry-
plate process “which could produce a photograph in full sunlight of
a street scene, including action and movement.”

In the sixties and the seventies of the last century such collodion
dry plates, produced by one or the other of the foregoing methods,
were largely used in traveling or on excursions. They required very
long exposure, with physical development, and gave very beautiful
results, but made great demands on the operator’s experience and skill.
We cite two examples of the method of procedure in those days. The
photograph taken in Nagasaki, Japan, in 1 868, by W. Burger on his
travels (reproduced in the 1932 ed. of the Geschichte, p. 521) on a
tannin plate, which was prepared in Vienna and not exposed until nine
months later in Japan. The time of exposure was seven minutes with a
Voigtlander-Petzval portrait lens, working with a small aperture. An-
other tannin dry-plate photograph was made from a plate prepared by
the same photographer in Vienna, April, 1872. He exposed it on a jour-
ney to Sibera with Count Wilczek in September, 1872. The exposure

DRY COLLODION PROCESS

37 5

took one and a half hours in sunlight, owing to the loss of sensitiveness
due to long keeping. It was made by means of a Dallmeyer triplet lens
with the smallest diaphragm opening and was developed at Vienna,
in December, 1872, with pyrogallic acid and silver nitrate developer
(reproduced in 1932 ed. of the Geschichte, p. 522).

In 1917 the tannin process was resurrected for the production of
very small fine-grained diapositives (see Chapter LI on microphotog-
raphy).

Russell’s tannin process underwent numerous changes. Tannin was
replaced by gallic acid; morphine and other alkalies were introduced
as preservatives, and coatings of mixtures containing gum and sugar
as well as coffee and tea decoctions, beer and albumen, were tried,
without any essential progress being made.

The plates were developed at first (in the style of the old Talbo-
types) with pyrogallic acid with addition of silver nitrate and citric
or acetic acid and also by “physical development.” It is important to
note here the improvement in the development of such dry plates,
which always contained iodo-bromo-silver; the greatest advance in
the development of the negative was made by the introduction of the
alkaline pyrogallol developer.

Wardley, an assistant of the English photographer Mudd, recog-
nized that the collodion dry plate could be developed with pyrogallol,
without the addition of silver nitrate.

In 1861 Mudd reported, for the first time, that collodio-albumen
dry plates (with iodo-bromo-silver) could be developed in full detail
with pure aqueous pyrogallic acid ( '/ 2 per cent) without the addition
of silver nitrate and acid (Phot. News, V, 386; Kreutzer’s Zeitschr.,
1861, IV, 1 31). Later, however, the full credit for the discovery was
given by Mudd to his assistant Wardley. Wharton Simpson, on
October 23, 1861, called attention to the importance of this method of
development, as proving that dry plates could be developed without
the use of silver nitrate. The image developed on albumen plates rapidly
and quite perfectly, but had to be intensified with pyrogallol, silver
nitrate, and citric acid. According to Simpson this method of develop-
ment is also applicable to Fothergill’s plates, to tannin plates, and to
Norris’s dry plates; the latter do not contain any trace of free silver
nitrate (Brit. Jour., VIII, 376. Kreutzer’s Zeitschr., V, 102).

Anthony, in New York (1862), increased the sensitivity of dry col-
lodion plates by subjecting tannin plates before exposure to dilute

376 COLLODION EMULSION

ammonia vapors, while Glover did the same after the exposure. In the
same year Major Russell 5 and Leahy, probably urged by the observa-
tions mentioned above, discovered the alkaline pyro-developer, which
was superior to gallic acid or pyrogallol development; he used the
pyro-ammonia developer with additions of potassium bromide. This
furnished the most important improvement in the method of develop-
ment, which did not reach its full use until the emulsion process
began. Russell pursued his discovery with a definite purpose, and to
his work is due the credit for the introduction of alkaline developers,
without which modem photography with silver bromide emulsions
could not have been accomplished in its initial period. 8

In the second edition of Major C. Russell’s work The T annin Process
(1863) we find described the action of ammonia in the developer, as
well as the part which addition of potassium bromide plays as retard-
ing agent; alkaline carbonates were also used in pyro-developers at
that time. Especially remarkable is Russell’s observation, which he
made during the continued experiments with his alkaline developer
and published later, that it is necessary to add ample bromine salts to
the iodo-bromo collodion; in fact, he finally succeeded in producing
a chemically pure bromine collodion ( Handbuch , 1927, Vol. II, Part
2). He recognized, therefore, the superiority of silver bromide over
silver iodide in the so-called “chemical development,” an experience
which later (in the emulsion process) was universally confirmed.

Chapter XLVIII. invention of collodion

EMULSION

The possibility of making a light-sensitive emulsion with silver salt
which would result in dispensing with the silver used for sensitizing
bath was first suggested by M. Gaudin, in La Lumiere (August 20,
1853). “The whole future of photography seemed to require a sen-
sitive collodion which could be preserved in a flask and poured when
required upon glass or paper and by the use of which, either at once
or after the lapse of time, positive or negative pictures could be ob-
tained.” Even then he evidently had in mind the silver iodide or silver
chloride emulsion, which he described in April, 1861, and called
“photogen.” 1 This he produced by mixing iodized collodion (or

COLLODION EMULSION

111

chloro-ammonium collodion) with nitrate of silver or silver fluoride.
The first collodion emulsion, in the real sense of the word, Gaudin
found at times as sensitive as wet plates, and he believed that it could be
used to especial advantage on paper in the camera. For silver chloride
collodion, which he produced with ammonium chloride and silver ni-
trate, he visioned its use in place of ordinary silvered positive paper.

Shortly before this (March, 1 86 1 ) , Bellini had recommended to
photographers, in the periodical Ulnvention, an ether-alcohol shel-
lac or sandarac solution, which contained iodo-bromo silver together
with lactate of silver and iron iodide. At the same time, the emulsion
process made its appearance in England, where it was kept secret.
Sutton wrote repeatedly of the good results which were obtained by
this process without a silver bath. 2 This process was patented in Eng-
land, April 29, 1 86 1, 3 by Captain Henry Dixon.

SILVER BROMIDE COLLODION EMULSION

A serviceable independent process introduced about this time was
the silver bromide emulsion process with collodion (“photography
without silver bath”), discovered in September, 1864, by B. J. Sayce 4
and W. B. Bolton 5 in Liverpool and described in detail later in the
Photographic News. They used Russell’s pyrogallol and ammonia
developer. In a later, not essentially different, formula in 1865 Sayce
enumerates almost all possible modifications of collodion emulsion.
Sayce also, in 1865, put forward the idea of separately precipitating
and washing the silver bromide and preparing the emulsion sub-
sequently.

The American Carey Lea (1823-1897) made notable photochemi-
cal studies on collodion developers and, later, on various molecular
states of silver. He joined the Chemical Section of the Franklin Insti-
tute, Philadelphia. Ill health interrupted his chemical work, and he was
compelled to seek recovery by extended travel in Europe. He spent
some time in Italy and in the Tyrolean Engadine. He was a lover of art,
and on his travels he gathered examples of paintings which enabled him
to have one of the finest art collections of that time in America. From
1864 he devoted himself zealously to photography, worked a great
deal with the formation of silver bromide, with silver iodide and silver
chloride by various developing substances, and studied the modifica-
tions of metallic silver. 6

Silver bromide emulsion with excess of silver nitrate was always

378 COLLODION EMULSION

combined in the early days with a preservative. Sutton published in
1871 a silver bromide collodion process 7 without a preservative, which
consisted only of an unwashed emulsion produced with a slight excess
of silver nitrate.

The discoverers of the silver bromide emulsion process had already
used in their early experiments Russell’s alkaline pyrogallic developer.

In the British Journal of Photography, January 16, 1874, W. B.
Bolton recommended washing silver bromide collodion by precipi-
tating it in a great excess of water. Canon Beechey published, in the
British Journal of Photography, October 1, 1875, a method of pro-
ducing silver bromide collodion plates with pyrogallic acid as a pre-
servative and arranged to have them manufactured for the market.
These collodion dry plates, however, were only used for landscapes;
they could not compete with the greater sensitivity of wet plates and
therefore found no acceptance in portrait studios. No noticeable prog-
ress occurred in the years following, notwithstanding the many en-
deavors of the Englishman Abney, the American Carey Lea, the
Russian Warnerke, then living in England, the Frenchman Chardon,
and others to popularize the new plates. Nor were the prize competi-
tions of different photographic societies and other encouragements of
the art of any avail.

In 1874 Newton announced that an extract of mustard seed and
mustard oil could be used in sensitizing silver bromide collodion plates.
This observation, which remained at that time unnoticed, became later
very important, when Sheppard, of the Eastman Kodak Research
Laboratory, Rochester, U.S.A., recognized mustard oil and related
sulphurous preparations as sensitizers for silver bromide gelatine and
took out patents for this use of sulphurous compounds ( Handbuch ,
1927, II (1), 509). The increased sensitivity of silver bromide collodion
by addition of ammonia was first published by the author in June,
1880 {Phot. Korr., XVII, 146). Collodion emulsion was later displaced
in portrait and landscape photography by gelatine dry plates.

In reproduction photography, however, new fields were opened
for silver bromide collodion by Dr. Eugen Albert’s invention of
orthochromatic collodion emulsion, the production of which became
an important industry with its origin in Albert’s establishment at
Munich.

Dr. Eugen Albert (1856-1929) was the son of Josef Albert, the
inventer of collotype printing with cylinder machines. He studied

COLLODION EMULSION

379

physics and chemistry in Munich and wrote a dissertation: “On the
Change of Color T ones in Spectral and Pigment Colors under Diminish-
ing Intensity of Light.” In the very same year (1882) he perfected his
experiments in the production of a highly sensitive silver bromide
collodion emulsion to such an extent that he realized its excellent
quality for the reproduction of paintings and its possession of a high
sensitivity for colors such as had been unknown up to that time.

He had achieved this increased color-sensitivity with ethyl eosin
silver nitrate. He founded the Munich art and publishing house of
Dr. E. Albert & Co., in 1883. For reproduction he at first made use
of platinum prints but later adopted Dujardin’s heliogravure method
( Handbuch , 1929, IV (3), 29). It was not until 1888 that he introduced
on the market his washed silver bromide collodion emulsion, which
he made highly sensitive with eosine silver (ethyl eosine) and demon-
strated, by invitation of the author, on May 17, 1888 in the photo-
graphic studio of the Graphische Lehr- und Versuchsanstalt, Vienna.
He there proved the high sensitivity of his emulsion by taking a portrait
with an exposure which, though longer than on a gelatine silver bro-
mide plate, was yet three times faster than the most rapid wet collodion
plate. He used a washed silver bromide collodion emulsion, which was
made up with an excess of alkaline bromide, but it was in no way
more sensitive than the earlier emulsions of this kind. It received its
enormous sensitivity for light and color only from the addition of the
eosine preparation ( Handbuch , 1927, II ( 2 ) , 203).

This invention of Albert’s “isochromatic collodion emulsion” proved
to be of permanent value in certain classes of reproduction photography
(paintings, three-color process, halftone negatives 8 ; it has become
a special branch of the photochemical industry, first in Munich and
later in England. Unfortunately, these isochromatic collodion emul-
sions must be used moist, and the problem of finding a good sensitive
dry plate was not solved by this method. The solution of that problem
was found only in the gelatine silver bromide dry plate.

Chapter XLIX. invention of collodion

LAYERS FOR THE PRODUCTION OF STRIPPING
FILMS ON SPOOLS

The paper holders for calotype photography must be regarded as
the precursors of the roll holder. In the beginning of 1870 many
investigators, trying to improve the collodion dry-plate process, sought
a solution of their problem in the form of silver bromide collodion.
L. Warnerke, 1 who experimented in the production of silver bromide
collodion emulsion with an excess of silver nitrate, developed with
pyrogallol and ammonium carbonate, received a prize (1877) from the
Association Beige de Photographic ( Handbuch , 1927, 11(2), 200 and
3 1 1 ) . He had in 1 875 invented a film-roll holder. He produced in that
year (Phot. News, 1875, Nos. 876, 877) silver bromide films on
gelatinized paper and exposed them in roll holders. He used a base of
alternate collodion and india rubber coatings, on which he flowed the
collodion emulsion. When finished, he strengthened the film with a
gelatine coating and stripped it off the paper. In this roll holder of
Wamerke’s it is easy to recognize the original model of the Kodak
and other modern film-roll holders. Later, as we know, gelatine bromo-
silver emulsion was also applied to paper and cardboard (Milmson,
1877, Ferran and Pauli, 1880, Lumiere).

Warnerke’s predecessors in the invention of the roller dark-slide
were the Englishmen Melhuish and Spencer, who patented a “roll
holder” May 22, 1854; this was intended for Talbotype negative paper.
Warnerke was the first to use “stripping films” with a roller dark-slide.
The Warnerke roller dark-slide is similar to the Eastman roll holder.
This was not recognized by George Eastman (see George Eastman,
by C. W. Ackerman, 1930, p. 50) when his attention was called to it.

But all these methods were displaced by the introduction of gelatine
silver bromide and have only a historic interest. The Eastman Kodak
Company’s stripping roll-paper, with gelatine silver bromide emulsion,
came into general use in 1884 under the name “stripping film” (Hand-
buch, 1930, III (2), 395)-

Chapter L. stereoscopic photography

We have already described the principles of stereoscopic vision in
Chapter VI. Shortly before the invention of daguerreotypy (1838)
Sir Charles Wheatstone (1802-1875) invented the mirror, or reflecting
stereoscope. He tried to produce a relief impression by drawing, side
by side, two dissimilar images of an object; one represented it as
seen by the right eye, the other, as seen by the left. The experiment was
successful. The figures were drawn by hand and consisted of simple
lines and circles. It was more difficult, of course, to obtain stereoscopic
pictures of persons and landscapes, but the invention of photography
made this possible. The process of producing stereoscopic pictures
by taking two views of the same object, of which the foci were to
some extent equidistant from the median line, was announced in 1 844
by Professor Ludwig Moser, of Konigsberg. It was not discovered
by J. Duboscq, as Moigno stated earlier (Dove, Repert. d. Phys.,
1856, p. 238; W. Dost, Phot. Cbronik, 1928, p. 387).

David Brewster (1781-1868) replaced the mirrors by lens-shaped,
curved prisms (1844); this produced a much handier stereoscope,
which Helmholtz later improved.

In The Times of October, 1856, appeared letters from Wheatstone
and Brewster on the history of the invention of the stereoscope pro-
voked by an assertion made in this newspaper that James Elliot had
invented the stereoscope as early as 1834, but had not constructed
one until 1839. This took the form of two small openings in a card.
Wheatstone, however, claimed the credit for the invention of the
stereoscope and pointed to his publication in the Philosophical
Transactions of 1838. Brewster maintained that Euclid, Galen, Porta,
Aguilonius had asserted that the different images of an object
created in the two eyes unite to produce a relief effect. Wheatstone,
however, insisted on his claim to priority (Kreutzer’s Jahresbericht
iiber Fortschr. d. Phot., 1857, p. 537). 1

In the Wicar Museum at Lille can be found two pen and ink drawings
which represent a young man seated on a bench drawing with com-
passes. These drawings are by Jacopo Chimeti, a painter of the Floren-
tine School, 1554-1640. These two drawings represent the same subject
from two different positions; one of them a little to the right, the other
more to the left. Both pictures are of such identical dimensions that
they can be united in a stereoscopic view of the whole; this would

382 STEREOSCOPIC PHOTOGRAPHY

lead one to believe that they were designed especially for this parti-
cular mode of viewing (Phot. Korr., 1897, p. 554).

Brewster first described his lenticular stereoscope in April, 1844,
before the Royal Society at Edinburgh, and had constructed a “double-
eyed camera [Binocular] for the taking of portraits and copying
statues” in Edinburgh (1844). This attracted, at the time, very little
interest. Only when Brewster, in 1850, brought to Paris a model of
the instrument made in Scotland and demonstrated it to the Abbe
Moigno, the distinguished author of the work Antique moderne and to
the opticians Soleil and his son-in-law Duboscq was the value of his
instrument fully recognized, as Brewster himself relates. Duboscq at
once began to manufacture the lens stereoscope for the market, and he
produced a series of most beautiful stereoscopic daguerreotypes of per-
sons, statues, bouquets of flowers, and objects of natural history,
which thousands of persons flocked to see.

Daguerreotypy was early used for the production of stereoscopic
photographs, and they were subjects of production in many photo-
graphic studios at the end of the forties and in the beginning of the
fifties of the last century. Small stereoscopic daguerreotype portraits
were mounted on cardboard so that they could be set up opposite a
pair of simple condensing lenses, which made the stereoscopic viewing
of the pictures possible. The whole outfit could be folded into its
case and took up no more space than a memorandum book. 2

In England the stereoscope became popular after having been
brought back from Paris in 1851. 3 It attracted the attention of the
queen at the Crystal Palace Exposition, London, 1851, and in conse-
quence the demand for the stereoscopes rose enormously. An illustrated
announcement of a sale of stereoscopic pictures in 1848 demonstrates
the zeal employed in Paris in the popular distribution of stereoscopic
pictures 4 (reproduced in 1932 ed. of Geschichte, p. 535).

Stereoscopic pictures were also produced on Talbotype paper in
the fifties, but daguerreotypes, owing to the skilled technique then
prevailing in that art, far excelled them in beauty and therefore found
more favor with the public.

The introduction of the collodion process made possible the mass
production of stereoscopic pictures. In particular, it was the English
Photographic and Stereoscopic Company which had the monopoly of
photographing art and industrial objects of the London World Expo-
sition of 1862, and they disseminated beautiful stereoscopic pictures

STEREOSCOPIC PHOTOGRAPHY 383

in all stores of Europe. The further introduction of stereoscopic photog-
raphy was later materially advanced by the invention of silver bromide
dry plates, and stereoscopy found many applications in the various
branches of arts and sciences, of which we only mention its use in
microscopy, photogrammetry, radiography, and the experiments for
the introduction of stereoscopy in the projection process. 5

Among modern types of stereoscopic apparatus which have appeared
may be mentioned Stolze’s orthostereoscope, 8 Schell’s universal stereo-
scope, and Zeiss’s stereoscope.

Referring to stereoscopic projection, Brandner calls attention to the
early publication of Tissandier’s Merveilles de la phot. (Paris, 1858),
to Claudet’s Le Stereoscope, and to Blanchere’s Monographie du stereo-
scope in which Claudet’s “monostereoscope” is described (Brit. Journ.
Phot., 1907, p. 246).

F. P. Liesegang, in Prometheus (191 1, p. 588), writes on the history
of stereoscopic projection: D’ Almeida 7 reported in 1858 a stereoscopic
process which consisted in producing the component pictures in com-
plementary colors (for instance, red and green), and viewing them
through spectacles with glasses colored similarly, looking through the
red glass upon the green picture and through the green glass on the red
one. He supplemented this by giving a method of combining stereo-
scope with the phenakistiscope, a precursor of the cinematograph, in
which small electromagnets screened the eye intermittently. The idea
came to the surface again in later years, when two complementary
stereoscopic pictures were thrown on a screen by two projection
lanterns, so that they appeared to the eye in rapid succession by means
of rotating shutters. Each person in the audience received a spectacle-
like instrument, which also at equal speed covered first the right and
then the left eye, exposing to view only the respective complementary
stereoscopic half of the picture. This process of stereoscopic projection
was elaborated by W. B. Woodbury (1881), A. Stroh (1886), F. C.
Porter (1897), August Rateau (1899), who tried to make cinemato-
graphic projections of this kind; then by Doyen, Schmidt, and Dupuis,
who employed, in 1903, rotating mirrors for the same purpose, and
then by Jager, in 1905, who used rotating diaphragms, and finally by
M. Topp, in 191 1.

“Parallax stereograms” are credited by Clerc (Brit. Jour. Phot.,
1926, p. 88) and in earlier publications by E. J. Wall, to H. Berthier,
1 896. They are later contained in a patent by Jacobsen ( 1 899) . Frederic

384 STEREOSCOPIC PHOTOGRAPHY

Eugene Ives reports that he made this invention as early as 1885 (doc-
umentary evidence for this not available), but that he did not use it
commercially until 1902, in which year he patented it; he was unaware
of Berthier’s work (Brit. Jour. Phot., 1926, p. 218). At any rate, F. E.
Ives deserves credit, more than any other, for the introduction of the
parallax stereogram.

[[A further development of the use of gratings to produce photographs ex-
hibiting stereoscopic relief is the “parallax panoramagram” which exhibits
a picture which continuously changes its appearance throughout a wide
range of observing angles and positions. Such pictures were first made by
C W. Kanolt (U. S. Pat. 1,260,682, Mar. 26, 1918) by using a camera
which moved through a wide arc during exposure. This form of relief
picture has been exhaustively studied by Herbert E. Ives, who developed
a number of methods of making them, particularly by single exposures
with a large diameter lens or concave mirror ( Journal of the Optical So-
ciety of America, 1928 et seq.). He has projected a series of such pictures
on a lenticular rod screen, thereby achieving experimentally the projec-
tion of motion pictures in relief without resort to apparatus at the eyes of
the observers ( Journal Soc. Motion Picture Engineers, July, 1933). Trans-
lator’s addition.]

INVENTION OF ROENTGEN STEREOSCOPY

It is not generally known that the Austrian physicist Ernst Mach 8
is the inventor of Roentgen stereoscopy. Roentgen rays and Roentgen
photography were discovered in December, 1895, by the physicist
W. C. Roentgen (1845-1923), who received the Nobel prize in 1901.
In the spring of 1 896 Professor E. Mach, while inspecting Eder and
Valenta’s work in Roentgen photography at the Graphische Lehr-
und Versuchsanstalt, in Vienna, suggested, in a conversation with the
above-named workers, the production of stereoscopic Roentgen photo-
graphs by shifting the Roentgen tubes. Upon this suggestion they acted
in collaboration with E. Mach. In the richly illustrated work V ersuche
iiber die Photographie mit Rontgenstrahlen (Vienna, 1896) Eder and
Valenta published their work. We quote from this first monograph on
Roentgen photography, from which several full-page illustrations are
republished in Meyer’s Konversationslexikon (6th ed.).

The images obtained in the manner described by the aid of Roentgen
rays, are silhouettes, which show, as already mentioned, a certain degree
of apparent relief, because the varying degrees of transparency of the
layers are expressed in the picture. In order to attain completely this relief

MICROPHOTOGRAPHY

3 8 5

effect we experimented with stereoscopic exposures, employing Roentgen
rays according to Dr. E. Mach’s advice. For this purpose the object, a
mouse, was placed on a piece of mica stretched over two strips of wood
on a table, and the plate, wrapped in black paper, was slid under it, until
it touched the mica, but enabled the plate to be exchanged without mov-
ing the object lying on the mica. Then a ruler was fastened to the table
parallel to the edge of the plate, and the table was marked io cm. Qabout
4 inches] to the left and to the right of the center of the plate. The light
source, about 30 cm. [(about 1 2 inches] above the object, was placed at
first so that its center registered with one of these marks on the table;
then its axis was turned toward the object, and an exposure taken. The
plate under the object was now changed, and the light was moved so that
its center registered with the other mark, and the procedure was repeated.
The two pictures, viewed as diapositives in a mirror stereoscope, showed
a stereoscopic picture in astonishing relief of the skeleton of the mouse.
This method of photography may find approval after some improvements
in the apparatus are made, in particular when dealing with objects of
natural history. E. Mach was the first or at any rate one of the first, who
thought of Roentgen stereoscopy, and the first practical experiment was
made in the Eder and Valenta photochemical laboratory. Later
stereoscopy became of unexpected importance in surgery.

Chapter LI. microphotography

Of the many scientific applications of photography which followed
the improvement of the negative process, we mention in the following
chapters only a few characteristic branches: microphotography, photo-
grammetry, and balloon photography.

Microphotographs, that is, enlargements of microscopically small
objects, were first projected by Wedgwood, in 1802, on light-sensi-
tive silver paper by sunlight. These, however, he was unable to fix.
The earliest permanent (fixed) microphotographs on silver chloride
paper were probably made by J. B. Reade, of London, in the middle
of 1839. He used hypo as fixing agent; for instance, he made an en-
larged photograph of a flea and sold such pictures. 1 These enlarge-
ments were very imperfect.

Arago had pointed out the possibility of microphotography in his
report on Daguerre’s invention to the Chamber of Deputies, in 1839.

In that year the French scientist Alfred Donne took up this idea,
and, working with a microscope and daguerreotype plates in sunlight,

MICROPHOTOGRAPHY

386

he made enlarged pictures of the eye of a fly, specimens of which he
presented to the Academy of Science, Paris, in October, 1839. 2 In
February, 1840, Donne published other “microscope-daguerreotypes,”
made with a microphotographic apparatus introduced by the Paris
optician Soleil.

Alfred Donne (1801-1878), doctor of medicine, was head of the
clinic at the Charite in 1829, became subinspector of the administration
of mineral water establishment at Enghien; general inspector of the
medical faculty and rector of the Academy at Strassburg, and finally
at Montpellier. He published Corns de microscopie complem. d' etudes
medic, suivi d'un atlas (Paris, 1845).

In March, 1840, Chevalier also showed microphotographs ( Compt .
rend., 1840). Later progress in this field is reported by Monpillard
in his: “Notes sur l’histoixe de la photomicrographie” (in Musee
retrospect if de la classe 12. photographie; rapport du Comite d’ Instal-
lation de I’Exposition universelle, Paris, 1 poo).

Donne later employed a vertical microscope of Chevalier’s, by which
the emerging rays were projected by a prism with total reflection
horizontally into the photographic camera. In order to attain greater
sharpness, he inserted blue glass (to correct focal differences). He also
used a concave lens as projection-ocular in order to increase the magni-
fication (see Monpillard, cited above).

At about the same time, Dr. Josef Berres, professor of anatomy at
the University of Vienna, took up the use of the microscope for the
production of enlarged photographs on daguerreotype plates, and he
was probably one o f the first t o use artificial light in microphotography.
He obtained, as early as 1840, a microphotograph of the cross section
of a plant, made with Drummond’s calcium light; he reproduced this
by a process of etching daguerreotype plates, which he had invented,
and obtained prints with fatty inks on a printing press. He wrote about
his experiment in the Vienna Zeitung of April 18, 1840 (p. 737).

Josef Berres (1796-1844) was an assistant to a barber surgeon,
never acquired a doctor’s degree, and was called “doctor” only in an
honorary sense. When twenty-one years old he became professor of
anatomy at the University of Lemberg, where he distinguished him-
self by the production of many instructive anatomical preparations.
In 1830 he came to Vienna in the same capacity and published various
works on anatomy, the most important of which is his Anatomie der
mikroskopischen Gebilde des menschlichen Korpers (Vienna, 1837-

MICROPHOTOGRAPHY 387

1843). He used Pldssl’s instruments, was a skillful draftsman, and
drew the illustrations for his books himself. As soon as Daguerre’s in-
vention became known in Vienna, he acquainted himself with this
novel process and made use of it (Wurzback, Biogr. Lex., I, 333).

Donne, with Leon Foucault 3 as collaborator, published his Atlas
d'anatomie microscopique in 1 844. They made the original exposures
in Paris with the solar microscope on daguerreotype plates; but Donne
had to make drawings from these originals, because at that time it was
impossible to reproduce the photographs.

About the same time J. B. Dancer, in London, produced enlarged
objects by microphotography with the aid of the solar microscope, and
in 1841 Richard Hodgson also made good daguerreotype microscopic
enlargements.

Bertsch, of Paris, introduced, in 1851, the horizontal microphoto-
graphic apparatus. The Parisian optician Nachet also engaged in micro-
photography, about 1854, and produced ( 1856), with the collaboration
of Foucault and Duboscq, among other subjects, a microphotograph
of the blood of a frog on daguerreotype plates, which, by its extremely
fine definition, attracted much attention at the Paris Exposition of
1900. 4

When Talbot’s paper negative process became known and silver
chloride positives (prints) could be produced in any desired number,
this process was applied to microphotography. Carpenter is said to
have presented such microphotographs on paper (Talbotypes) to the
session of the British Association as early as 1847. 5 These, however,
were unsatisfactory, because the coarse grain of the paper negatives
interfered with the faithful reproduction of the delicate microscopic
structure. It was not until the introduction of photography on glass
(albumen and collodion processes) that photography became an im-
portant aid in microscopic research. As early as 1853 J. B. Dancer
produced microphotographic diapositives on collodion plates, which
he described in the Manchester Guardian. He was an optician in Man-
chester and exhibited in his house microphotographic diapositives,
some of which he had colored and are reputed to have been of an ex-
cellent quality (Phot. Jour., 1922, p. 497).

In the middle of the last century Professor J. J. Pohl, of the Poly-
technikum at Vienna, engaged in microphotography, which he called
“megatypy.” Others who worked along this line were Weselsky, in
Vienna, and in England, Hodgson, Shadbolt, Kingsley, Huxley, and

388 PHOTOMICROGRAPHY AND PROJECTION

Allen Wenham, whose progress kept pace with the general develop-
ment of optics and photography. All these men contributed greatly
to the highly important achievements of later years.

It was especially the introduction of the very completely corrected
apochromatic lenses and projection oculars of the optical establish-
ment of C. Zeiss, Jena, that enormously increased the efficiency of the
microscopic lens system. Orthochromatic gelatine silver bromide plates
and light filters of various kinds were also used in microphotography
at the end of the nineteenth century with great success; green, yellow,
and blue light filters were introduced, and photographs were taken for
special work with small spectral zones in the optically light part of the
spectrum. A. B. Stringer 8 used light of the extreme violet and ultraviolet
for special microphotographic exposures, which he exhibited to the
Royal Microscopic Society in April, 1903. In 1904 A. Kohler, 7 of the
staff of Carl Zeiss, developed a valuable method of photomicrography
by means of monochromatic ultraviolet radiations which were isolated
from spark discharges spectroscopically, so that they were free from
light of other wave lengths. 8

The progress of microphotography in recent years is recorded in
Eder’s photographic annuals ( Jahrbuch fiir Photograpbie ) ; also in the
work of Dr. Richard Neuhauss Die Mikrophotographie (Halle, 1894)
and his Lehrbuch der Mikrophotographie (2d ed., 1898); Dr. Kaiser-
ling, Lehrbuch der Mikrophotographie (Berlin, 1903); Marktanner-
Turneretscher, Die Mikrophotographie ah Hilfsmittel naturwissen-
schaftlicher Forschung (Halle, 1890); Pringle, Practical Photomicro-
graphy (3d ed., London, 1902); Monpillard, La Microphotographie
(Paris, 1899); and Mathet, Traite practique de photomicrographie
(Paris, 1900).

Chapter LII. photomicrography and pro-
jection

The extremely sharp definition of collodion images made possible
the production by Dancer of microscopically reduced pictures (photo-
micrographs) in 1856, as well as by Dagron, in Paris, about i860.

Dagron, made his microscopically reduced pictures with apparatus
constructed by the French optician Duboscq. These extremely mi-
nute photographs were made with Taupenot’s albumen-collodion

PHOTOMICROGRAPHY AND PROJECTION 389

dry-plate process and developed by the physical method. This method
of development gives extremely fine-grained images, which were ex-
amined with a magnifying glass. The “photographic magnifying-glass
pictures” were produced in France until the present day and were
called “Stanhopes.” “Stanhopes” were called after the English scien-
tist Lord Charles Stanhope (1753-1.816), who published many useful
technical inventions; for instance, Stanhope’s typographical printing
press, improvements in the stereotyping process, and, among other
things, the “Stanhope microscope lens,” which is still manufactured
and is used in small sizes for viewing the microscopic pictures under
discussion (see Kuchinka, in Phot. Korr., 1907, p. 409).

The minute photographs made by very few firms for sale under this
name are well known; they are mostly mounted in ornaments, watch
keys, etc., and they became mass products in commerce. The collodion
albumen process was used in this method. The manufacture of these
photographs spread widely, but in the sixties already complaints were
heard in Paris because they were employed for obscene pictures (Phot.
Arch., 1864, p. 138). The method of production of these “Stanhopes”
has changed only in some small particulars up to the present time. 1

John Benjamin Dancer was a prominent English worker in this
field and made a record in 1861 in the production of microscopically
small pictures when he succeeded in making a microphotograph of a
family group of seven persons on the head of a pin and taking ten
thousand images on a square inch (Brewster, Phot. Jour., 1 862 p. 1 27 ) .

The ingenious Paris photographer Dagron made a reputation for
himself not only by his microphotographs but also, during the Franco-
German War of 1870, through courageous balloon trips and the
organization of a mail service carried on by means of carrier pigeons
to and from Paris during the siege of that city by the Germans. In
this service he made an ascent from Paris with the balloon “Niepce,”
landed in Tours, and organized a carrier pigeon service, which de-
livered hundreds of thousands of messages to beleaguered Paris. The
news to be transmitted was printed on large sheets of paper, these were
pieced together, and a sharp negative on glass was made from the
printed matter. This was again reduced by the Dagron microphoto-
graphic method on a gelatine film, measuring only six square centi-
meters (about 2 Vi square inches). This tiny film, carrying the mes-
sage, was rolled up and inserted in a quill, which was fastened to the
wing of a carrier pigeon and was then sent from Paris to Tours. There,

39 o PHOTOMICROGRAPHY AND PROJECTION

as well as later in Bordeaux, similar gelatine films were made and
transmitted by the carrier pigeons returning to Paris (Lafollye, De-
peches par pigeons voyageurs pendant le siege de Paris, Tours, 1871 ) .
In Paris the dispatches were considerably enlarged in a darkroom
with Duboscq’s apparatus, projected on a white wall and deciphered.
A number of clerks were engaged in copying the contehts of the
photographic communications and dispatching them from there
through the open postal channels. All photographic government and
private dispatches which Dagron prepared at Tours and Paris were
completed for each carrier pigeon flight in two hours. Each film carried
copies of twelve to sixteen reduced folios and contained on an average
from three thousand to four thousand dispatches. The material used
in this correspondence was so light that one pigeon carried eighteen
films, which contained altogether about sixty thousand dispatches
and had a total weight of less than one gramme. In Paris and Tours
the dispatches arriving from both sides were copied, and millions of
copies were forwarded to the proper parties.

About 1898 Dr. Neubronner, court pharmacist, at Cronberg, Ba-
varia, installed a carrier pigeon riiail service for the transmission of
medical prescriptions between the hospital at Falkenstein and his
pharmacy. He employed also a carrier pigeon photographic apparatus
and a portable dovecote. This small camera, for from two to eight
exposures, was attached to the breast of the pigeon and acted auto-
matically during the flight of the bird in making photographs. This
invention was tested at the carrier pigeon station of the Ministry of
War at Spandau, but was found without practical value and is men-
tioned here merely as a curiosity (“Munch, neueste Nachrichten,” in
Phot. Chronik, 1898, p. 377).

Louis Jules Duboscq (1817-1886), to whom we owe numerous
progressive steps in the field of photography, also constructed an
apparatus for enlarging by electric light and presented it before the
Paris Photographic Society, February 15, 1861.

Duboscq also equipped a projector with a device for the projection
of horizontal objects by transmitted light, thus making them suitable
to the so-called vertical projection. He used this apparatus for the
demonstration of all kinds of physical and chemical experiments; mag-
netic lines of force, magnetic needles, crystallizations, etc. The Duboscq
vertical device was imperfect inasmuch as he applied the mirror,
which diverted the illuminating rays in the converging cone rays in

THE SOLAR CAMERA

39i

front of the condenser, which narrowed the range of vision. Professor
Henry Morton, of Philadelphia, improved this apparatus in the early
seventies.

M. Reiner, of Vienna, described, in 1 890, the electric “epidiascope”
in his book published by Alfred Holder, in Vienna, Arbeiten aus dem
Institute fiir allgemeine und experimented Patbologie des Prof. Dr.
S. Strieker. The name “epidiascope” was given by this university pro-
fessor of medicine, and the apparatus was constructed after his specifi-
cations. He used it with great success in his lectures at the university.
In the same publication mentioned above appears an article by Strieker
“Uber das elektrische Mikroskop mit auffallendem Lichte.” This made
the epidiascopic projection suitable for scientific lectures. The optical
works of Carl Zeiss, at Jena, produced, in 1 898, an epidiascope con-
structed by the engineer Edward Richter. In 1903 August Kohler
reported on an appliance for microprojection, manufactured by Zeiss.
This topic is dealt with in Zentral-Zeitung fur Optik und Mechanik
(1928, No. 25).

Chapter LEI. the solar camera

The earlier methods for the production of negatives on glass per-
mitted only exposures on paper or glass plates of small size, and enlarge-
ments were made from them on paper, linen, glass, and so forth.
The photographic papers and the other materials had only a limited
light-sensitivity; for this reason enlarging cameras were used with
direct sunlight and were called “solar cameras.” These enlarging earn-
er as were constructed af ter the principle stated by Davy in Chapter XV
and later described in Chapter LI.

Gatel made enlargements in July, 1854 ( Gazette du midi, July 8,
1854; Bull. Soc. frang. phot., VI, 70), in the following manner. He
inserted the negative in the camera, set up a reflecting screen and placed
the lens so close to the negative that he obtained an enlarged picture.

The American J. J. Woodward, in Baltimore, was the first to con-
structing 7, a well-designed enlarging apparatus in which he collected
sunlight by means of a plano-convex lens and used this condensed light
for the production of enlarged positives from small negatives. He
patented the apparatus in England (Sept. 22, 1857, No. 2459) and
brought it to the attention of the photographers in Paris and London in

THE SOLAR CAMERA

392

1859. The design of this apparatus was followed in all later solar
cameras. This theory was studied by Claudet (Bull. Soc. frang. phot.,

1860, p. 249) and Leon Foucault (Bull. Soc. frang. phot., 1861, VII, 1;
Kreutzer’s Zeitschr. f. Phot., 1861, III, 214); and others (for further
details see Handbuch, 1892, II (1), 662).

Wothly, a photographer in Aachen, made a practical improvement
on Woodward’s solar camera in 1 860 and exhibited portraits almost
life size, which had been enlarged with a solar camera, at the session
of the French Academy of Sciences, October 8, i860 (Compt. rend.,
LI, 558), attracting much attention thereby. Disderi, in Paris, acquired
this process for twenty thousand francs in the same year, with the
privilege of being its sole user in France. This type of solar camera
consisted in the separation of the reflector from the apparatus, which
did away with the vibration caused by the turning of the mirror during
the exposure (illustrated in the 1932 ed. of the Geschichte, p. 550).

In the Deutsch. phot. Ztg. ( 1 909, p.453) it is mentioned that Wothly
had traveled to Aachen as an assistant to a bearkeeper, then turned
to photography and acquired great wealth and position. He was an
ardent equestrian, and on one occasion he was thrown from his horse
and broke his leg. He recovered, retired from business, and entrusted
his large fortune to a banker, who failed during Wothly’s absence on
a trip. He did not long survive this blow of fate. Wothly’s character
was dramatized in Speilhagen’s novel Der Sturmvogel.

Wothly’s solar camera was very large. The condenser had a diameter
of one meter (39.37 inches) and a focus of two meters (about 6'/ 2
feet). The sunlight was reflected on it by a large mirror. The author
acquired such an original apparatus in 1 890; it was in a workable con-
dition and was installed as an historic relic on the flat roof of the
Graphische Lehr- und Versuchsanstalt, Vienna, under his direction.
The enormous heat of the condensed rays of the sun made it necessary
to cool the rays with systematically arranged parallel water troughs.

With such solar apparatus all enlarging was done in the sixties and
the seventies. Generally the process introduced by Talbot and im-
proved by Blanquart-Evrard was employed in the preparation of the
paper, with solutions of iodides (possibly mixed with bromides or
chlorides) . The paper was then dried, sensitized in a silver bath con-
taining citric acid, and exposed from several minutes to a half-hour,
the faint image being developed with gallic or pyrogallic acid, with
the addition of citric acid, lead acetate, and so forth; or the enlargements

BALLOON PHOTOGRAPHY

393

were made on albumen paper, sometimes also on paper treated with
a pigment (about 1870 and later) which required several hours in the
solar camera; or a weak print was made on salted paper (silver
chloride) , which was used by artists and painters as a base for drawing
or painting, the pans not so covered being subsequently bleached
out with mercury bichloride.

Bensch improved Woodward’s condenser (i860), which consisted
of one collecting lens, by the addition of a second one; likewise
Monckhoven (1864), who called his apparatus “dialytic enlargement
apparatus,” improved it. In Vienna the court photographer, F. Luck-
hard, successfully employed such an apparatus in his studio.

We have treated this chapter somewhat in detail, because this phase
of the development of applied photography, long since forgotten,
was considered worth remembering.

The solar camera later disappeared entirely from the photographic
industry and was replaced by enlarging cameras with arc lamps.
Owing to the increased sensitivity of the silver bromide papers, other
sources of artificial light, still weaker, could be used.

Chapter LIV. balloon photography

The first suggestion of photography from a balloon in the air
appeared as a joke in a French lithographed caricature. Some years
later a satire was published by Andraud: Une Derniere annexe au
Palais cP Industrie (Paris, Guillaumin, 1855), in which the possibility
was pointed out for the first time that bird’s-eye views could be made
by photography from a captive balloon. Andraud confined himself
solely to the expression of what then seemed a purely fantastic idea,
without dreaming that it would ever be realized. 1

Without having any knowledge of this book, the photographer
Gaspard Felix Tournachon, of Paris, who called himself Nadar, 2
decided, in 1858, to ascend in a captive balloon in order to obtain
photographic bird’s-eye views of the earth. He planned to produce an
exact topographic map by photography from his captive balloon at
a height of several hundred meters. In order to secure for himself the
fruits of his project, Nadarapplied f or patents in France, England, 3 and
other countries.

In carrying out his plans for photography from a balloon Nadar

BALLOON PHOTOGRAPHY

394

met with many difficulties; he used the wet collodion process and
tried to prepare his plates in a small photographic darkroom, lighted
by an orange-colored linen window in the balloon; the hydrogen gas
with which the balloon was inflated contained hydrogen sulphide,
and this and other defects had a bad effect on the silvered collodion
plates. Notwithstanding all this, he succeeded in making a photograph
of the village of Petit Bicetre, in which, despite spots and small defects
in the negative, the houses can be clearly recognized.

CARICATURE OF BALLOON PHOTOGRAPHY

Honore Daumier, the artist, one of the best-known Paris person-
alities of his time, was urged by the balloon ascensions of the photog-
rapher Nadar, in 1862, to draw a caricature of the balloons with the
caption that Nadar had elevated photography to the “highest” art.
This was later printed in Paris photographe, a journal published by
Nadar’s son.

Nadar was requested, in 1859, to make balloon photography ser-
viceable for military purposes during the Franco-Italian War, but on
the one hand he did not have sufficient confidence that his process
could be successfully operated in the campaign, while on the other,
being a radical republican, he did not care to follow Napoleon III in
his expedition.

The first successful photographs from a captive balloon were made
in America, in October, i860, by the aeronaut Professor Samuel A.
King and the photographer J. W. Black, employees of a Boston firm,
who photographed the City of Boston from a height of 1,200 feet on
wet collodion plates and under great difficulties, but with success, as
reported in the Boston Herald , October 16, i860. An especially suc-
cessful balloon photograph by King and Black, dated 1861, 4 was
preserved and was reproduced twenty-two years later in the Photo-
graphic News, June 29, 1883.

In the American Civil War, however, the balloon was successfully
operated (1861) in finding the enemy’s positions, after General
McClellan had succeeded in employing the balloonists La Montain
and Allon. In 1862 the Union Army also used photography for recon-
naissance from a balloon, 3 during the siege of Richmond, Virginia.
From the negative of the terrain two prints were made, and each was
cut up into sixty-four numbered squares, of which one copy was left
with General McClellan, while the other was given to the balloonists.

BALLOON PHOTOGRAPHY

395

They ascended on June i, 1862, to three hundred and fifty meters
(about 1,378 feet) over the battlefield, got into telegraphic communi-
cation with headquarters, and reported the exact position and move-
ment of the enemy on the numbered squares of the map. General Mc-
Clellan’s success was greatly aided by the use of the balloon for
photography and telegraphy.

King and Black, of Boston, photographed their city as early as 1860-
1861 from a captive balloon. This photograph has been preserved and
is reproduced in the 1932 ed. of the Geschichte (p. 554). Negretti
photographed a London surburb in 1863 from a captive balloon. 8

Later the English physicists Glaisher and Coxwell made meteoro-
logical and photometrical experiments in high air strata and investi-
gated the speed of the blackening of photometric silver chloride paper
in order to gain important data for photometry.

James Glaisher ( 1 809-1903 ) , director of the magnetic and meteoro-
logical branch of the Greenwich Observatory, made several ascents
in the sixties in a free balloon. On one of these, in 1862, he was the first
to use collodion dry plates for his aerographic pictures ( Photographic
News, Sept., 1862). These dry plates were made by Hill Norris, of
Birmingham, according to his method of “preservation of the sensitivity
in collodion plates,” by coating them with a thin gelatine solution (to
keep them porous) and then drying them. The sensitivity was sufficient
for instantaneous exposures, which overcame the difficulty of the
swaying and turning of the balloon. Glaisher ascended, in 1863, to a
height of 2,000 feet and also used the Norris collodion dry plates.

In 1868 Nadar resumed his experiments at the Hippodrome in Paris
and used Henri Giffard’s balloon, guided by Arnaud, the balloon being
raised to two hundred meters (about 660 feet). Nadar succeeded in
making a brilliantly defined photograph of the Arc de Triomph, with
its details, from this balloon. These are among the best results obtained
in this field with wet collodion process.

When gelatine dry plates were introduced, the working procedure
became more simple. The first trials with such plates from a free bal-
loon were made by Triboulet, over Paris, on July 8, 1879, at a height
of five hundred meters (1,640 feet) ; unfortunately, the officials at the
octroi office (city tollgate) opened the plate holders in order to inspect
the contents and thus destroyed his exposures. The first successful
photographs on gelatine silver bromide plates from a free balloon were
made by Desmarets, June 14, 1880, who obtained excellent negatives

396 BALLOON PHOTOGRAPHY

with a lens of twenty-four cm. (about 9 / 2 inches) focus and instan-
taneous shutter. Desmarets photographed, in 1 880, the earth from a
height of 1,100 metres (about 3,609 feet), and, with a camera pointed
skyward, the clouds from 1,300 metres (about 4,265 feet). This re-
markable photograph is to be found in the Museum of Arts and Trades
in Paris. Then followed Cecil V. Shadbolt and W. Dale (1883), in
England, V. Silberer, in Vienna (1885), 7 and others. A. Batut ex-
perimented (1887) in aerial photography by means of a kite to which
a camera was attached, the exposure being made when it arose into the
air, 8 and numerous experiments of the most recent times followed in
the wake. 9

Cecil V. Shadbolt undertook, in 1883 and 1884, numerous ascents
in England with his balloon “Monarch,” photographing on gelatine
silver bromide plates. The camera was fastened to the gondola in a
most primitive manner.

Gaston Tissandier, editor of La Nature, made a balloon ascent near
Paris on June 1 5, 1 885, with Jacques Ducom, an accomplished amateur.
The photographic apparatus was fixed to the edge of the gondola; size
of plates, 13X18 cm. (about 5X7 inches) ; rectilinear lens of thirty-
five cm. (about 1 3 % inches) focus; exposures, one-fiftieth of a second.

The tragic fate of S. A. Andree’s balloon expedition to the North
Pole in 1897 is well known. The balloon was destroyed and all its
passengers perished. The relics of this expedition were found thirty-
three years later in the icy waste of White Island. The Kodak film
rolls, which had been buried under ice and snow, were developed into
serviceable negatives by John Hertzberg, in Stockholm.

E. Dolezal reports on the history of balloon photography in the
annals of the Society for the Dissemination of Knowledge in Natural
Science, Vienna, 1910. Further numerous reports on this subject are
contained in the author’s Jabrbucb fiir Photographie.

Thiele, in Moscow (1903), constructed a combination of seven
cameras for panoramic exposures from balloons. In the balloon cameras
of Muller and Klein (German patent No. 2049 1 5 ) the lens tilted down-
ward and described a circle during the panoramic exposure. In the
aerial photography of the past half century the airplane has largely
displaced balloon and kite. This use of the airplane was first attempted
about 1910 and was intensively developed in the World War 1914-
1918; since then it has found increasing use in the making of topo-
graphical and commercial surveys (see Chapter LV).

BALLOON PHOTOGRAPHY

397

Professor Karl Gunther, of Vienna, was the first to suggest the use
of a small captive balloon carrying, not a person, but only a photo-
graphic camera; he desired to photograph the terrain and intended to
control the exposure from the earth by an electrical device.

Walter B. Woodbury proposed, in 1877, this same method, in which
also the opening and closing of the lens was to be controlled by an
electric instantaneous shutter and long guide wires from the ground.
He constructed this camera; it weighed, with accessories, about 6 kg.
(about 1 3 '/i lbs) and carried four photographic plates on a disk. These
were exposed by a one-quarter turn. A small electromagnet set the
instantaneous shutter, and another set in motion the disk with the
plates.

The English military authorities interested themselves in Wood-
bury’s apparatus, and Lieutenant Baden-Powell lectured, in 1883, be-
fore the Royal United Service Institution in London, but the idea was
never applied in practice. Woodbury constructed only one camera
for himself, which he never put into practical use ( Photographic News,
1883, p. 400).

Kites were employed as early as the eighteenth century for scien-
tific purposes (Wilson, 1748; Franklin, 1752). Photography with un-
manned kites was tried by A. Batut, in 1887, and improved by the
Russian R. Thiele. The use of a rocket camera was proposed by the
Frenchman Denisse, in 1888; the German engineer Alfred Maul carried
out the rocket apparatus in practice and was granted a German patent
No. 162433, June 3, 1903.

The world record in photography from a balloon was achieved by
Professor August Piccard, born in Zurich, Switzerland (1884). In
1915 he became assistant professor and in 1917 full professor at the
Technical College, Zurich. In 1922 he was appointed professor of
physics to the University of Brussels. His principal scientific investi-
gations were in the field of magnetic and radio active measurements,
as well as the action of the rays or their penetration, which can only be
observed at great altitudes. For this study Piccard undertook his famous
flight into the stratosphere. He achieved an altitude of more than
16,000 meters. He used a spherical hermetically enclosed gondola of
aluminum constructed in Augsburg (Bavaria) . He ascended from there
on May 27, 1931, and landed on a glacier in Tirol. For his photo-
graphic exposures he used panchromatic dry plates made by Perutz,
in Munich.

PHOTOGRAMMETRY

398

Piccard’s second flight, on August 18, 1932, in which he used a
spherical gondola constructed in Belgium, was made from Zurich, and
he landed near the Lake of Garda, in upper Italy. Piccard’s original
reports appeared in the Compt. rend. (1932, Vol. CXCV; see also Die
Natur'ivissenschaften, 1932). In the summer of 1932 Piccard traveled
by way of France to the United States in order to prepare for other
ascents. A modern French caricature shows the famous Piccard, bal-
loonist to the stratosphere, leaving for America. Thus history repeats
itself.

Here must also be mentioned the physicist Erich Regener, Techni-
cal High School, Stuttgart, who made, in 1932, measurements with
small unmanned rubber balloons, which rose to a height of 20,000
meters. The measurements were automatically registered by photog-
raphy. Regener furnished the exact proof that the intensity of the rays
in great altitudes, contrary to earlier opinions, is considerably reduced
in altitudes higher than 12,000 meters.

Chapter LV. photogrammetry

The fundamental mathematical idea of constructing geometrical
plans from correctly drawn landscapes in perspective was first an-
nounced by Lambert (d. 1772) in Strasbourg. The Frenchman Beau-
temps-Beaupre in the year 1791-1793, executed topographical maps
(freehand drawings) of a strip of the coast of Van Diemen’s Land and
of the Island of Santa Cruz, which he visited at the time. When later,
1837-1840, a French expedition was sent by Dumont-d’Urville com-
manding the corvettes “L’Astrolabe” and “Zelee,” Beautemps-Beaupre
had already worked out, in 1835, instructions to the naval officers and
the hydrographic engineers, in which were laid down the principles of
the picture-measuring method. Thus, the process of making measure-
ments from pictures was known before the invention of photography.

When Arago ( 1839), in his memorable address on the discovery of
daguerreotypy, spoke of the remarkable possibilities of the new art,
he mentioned “the rapid method which topography might borrow
from the photographic process.”

As a scientific method, photogrammetry was first developed and
introduced into practice about 1851 by Aime Laussedat, an officer
in the French Engineers’ Corps, who later became colonel and honor-

PHOTOGRAMMETRY

399

ary director of the School for the Arts and Trades, Paris. We may call
him the father of this process.

Laussedat’s first important publication on the principles of photo-
grammetry appeared in 1854 under the title “Memoire sur l’emploi
de la chambre claire dans les reconnaissances topographiques.” It was
published in Memorial de I'ofjicier du genie (No. i6) \ redige par les
soins du Comite des fortifications, which report was continued in No.
17 (Paris, 1864). In Nadar’s Paris pbotographe (1891-1893) Laussedat
himself relates the history of his work. 1 Numerous excellent illustra-
tions of his early photogrammctric instruments, as well as the first
photographic exposures made in France, can be found there.

The first simple model used by A. Laussedat, in 1859, for photo-
grammetric exposures was constructed by the mechanic Brumer, in
Paris. The French government purchased five of these cameras. 2 A map
of the village of Buc, near Versailles, was made photogrammetrically
in May, 1 8 6 1 , on the scale of 1 : z ,ooo. 3

Laussedat took photographs of parts of Paris, in 1861, from the roof
of the Polytechnical College and from the church of St. Sulpice and
drafted plans from them which in exactness were in no manner in-
ferior to the existing plans; in this one perceives the beginning of photo-
grammetry for architectural subjects. The Ministry of War took up
the method for the French government, which was the first of all
nations to introduce it.

We quote from the biography of Laussedat written for the author’s
Jahrbuch (1907, p. 217) by E. Dolezal, professor of photogrammetry
at the Technical College, Vienna:

Aime Laussedat was bom in Moulins, France, on April 18, 1819, and
died in Paris, March 18, 1907. He became an officer, served with the en-
gineers, and eventually became a colonel.

As an officer in the Technical Corps he devoted himself largely to
geodetic work and turned to topography which attracted him greatly. As
early as 1850 he made his first experiments in applying photography to
ground maps, after he had already greatly improved the camera lucida.
He is the inventor of a telemetrograph for great distances (1850), which
he used during the War of 1870. In i860 he constructed his horizontal
photoheliograph.

Laussedat became professor of practical geometry at the Conservatory
for the Arts and Trades and professor of topography at the Polytechnical
College, Paris. He was director of the first-named institution from 1881-
1890.

400

PHOTOGRAMMETRY

Laussedat was very prolific in his literary work; from his pen came
numerous publications on photogrammetry, geodesy, astronomy, and
aeronautics; his works are to be found in the Compt. rend., the official
organ of the Paris Academy, and in other photographic journals and in-
dependent publications.

His labors received due acknowledgment in the many honors bestowed
upon him; we mention only that in 1879 he was made a Commander of
the Legion of Honor, that he was elected a member of the Academy in
1883, and that the government entrusted him during his long life with
many state and scientific missions. A monument erected to him at his
birthplace, Moulins (Allier), was dedicated on October 15, 1911 (Bull.
Soc. f rang . phot., 1911, pp. 287, 367).

Colonel Laussedat was for decades the interpreter of all the practical
applications of photogrammetry to topography in architecture, meteor-
ology, aeronautics, and of all efforts tending toward this use; even in his
last years he permitted no chance to pass without pointing out to his
countrymen, in lectures and articles, the progress of photogrammetry and
of stereophotogrammetry . 4

In Germany Albrecht Meydenbauer (1834-1921) devoted himself
to the application of photogrammetry for the preservation of histori-
cal monuments. He was a civil engineer and architect. The war
department, on the recommendation of General Wasserschleben, en-
trusted him, in 1867, with the project of experimental photographic
work and placed at his disposal the necessary means. He made photo-
graphs of Freyburg and its environments and became (1885) the head
of his own photogrammetrical institute (“Preussische Messbildan-
stalt”), which was supported by the Prussian department of education
and directed by him until 1909. In the archives for historical monu-
ments at this institute Meydenbauer recorded one thousand monuments
in Prussia by the photographic method, working along the lines of
historic art and archeological science. He later introduced success-
fully the method of “stand development” associated with his name.
In this method a very dilute developer is employed, especially advan-
tageous for interior exposures with great light contrasts; he used pyro-
gallol and later rodinal.

In Italy Professor Porro worked from 1855 on the improvement
of photogeodesy. In 1875 mapmaking was done in Italy by the general
staff (Lieutenant Manzi, later by Paganini) . Then followed, in Austria,
Vincent Pollack, chief engineer of the state railroads, Professor Schell,
at the Technical College in Vienna, in particular Professor Dolezal,

PHOTOGRAMMETRY

401

at the Mining Academy at Leoben, later at the Technical College in
Vienna, who was also the founder of the International Archives for
Photogrammetry, then Colonel Baron Arthur von Hiibl of the Mili-
tary Geographic Institute, at Vienna; in Germany Professor Koppe,
at Brunswick, and others. England, as well as other countries followed
with the introduction of photogrammetry. 6

Photography from airplanes, photographs by flyers, and aerophoto-
grammetry found their most extensive use and an unexpected impor-
tance in the World War. They are also extraordinarily important in
mapmaking and surveys during times of peace. Photographs from air-
planes are usually distorted by the tilting of the camera (the inclined
axis of the camera) . These distortions must be rectified or corrected
so that the photographs, when worked out, correspond to views taken
vertically. In all these exposures the optical apparatus for the correction
of distortion followed the principle of oblique correction introduced
by Captain Theodor Scheimpflug and became very efficient.

Theodor Scheimpflug (1865-1911) studied at the Austrian Naval
Academy, in Pola, and became lieutenant in the navy in 1898. He de-
voted himself to photography and allied sciences. Hoping to find
recognition for his scientifically based ideas, he applied, in 1897, for
transfer to the Military Geographic Institute, in Vienna. There he
studied geodesy and photogrammetry under Professor Dolezal, was
definitely transferred to the army as captain in 1898, and detailed to
the institute. Unfortunately, he found no real sympathy for his ideas
dealing with the photographic correction of oblique pictures by the
transformation of the aerophotogramme. He found so little support
that he applied to the director of the Graphische Lehr- und Ver-
suchsanstalt, in Vienna for an opportunity to do his experimental work
there, which was granted. He carried on his research independently.
In 1 906 he invented the photo-perspectograph and the first rectifica-
tion apparatus, developed the theory of photographic maps, and pub-
lished it in his dissertation Die Herstellung von Karten und Pldnen auf
photographischem Wege, which he read before the Vienna Academy
of Sciences in 1907. All this was of no avail; his work found no recog-
nition from the military authorities. Fortunately, having private means,
he continued his research. He wrote “Die Luftschiffahrt im Dienste
des Vermessungswesens,” in Horne’s Buck des Fluges (1911, Vol. I).

Theodor Scheimpflug recognized the importance of photogram-
metry in conjunction with his process for land surveys and wrote on

PHOTOGRAMMETRY

40 2

the technical and economic possibilities of an extended survey of the
colonies in the “Denkschrift der ersten Internationalen Luftschiffahrts-
ausstellung” at Frankfurt a. M., 1909 ( Wissenschaftliche Vortrdge,
Berlin, 1910, Vol. I).

Captain Scheimpflug’s work was that of a pioneer in the technique of
aerophotography and its scientific foundation; he received little per-
sonal glory, and the recognition due him was not bestowed upon him
until after his death (see Dolezal, “Th. Scheimpflug, sein Leben und
seine Arbeiten,” International Archiv fur Pbotogrammetrie, 1911;
Moffit, “A Method of Aerographic Mapping,” Geog. Review, 1920).
The Aero Club affixed a memorial tablet to his paternal home in Vienna.

Stereoscopy was applied in photogrammetry by Dr. C. Pulfrich,
of the scientific department of the Carl Zeiss works at Jena, in 1901,
and marked a great advance in photogrammetry. H e constructed the
stereocomparator, in which two stereophotographs of the two ends
of one base could be viewed stereoscopically, by which the position
and height of all those points of territory included in both photographs
could then be determined.

CarlPulfrich (1858-1928), the son of a teacher, studied physics and
mathematics in Bonn, established himself there in experimental physics
and constructed his well-known refractometer for chemists; Abbe en-
gaged him as collaborator, in 1890, for the Carl Zeiss works (depart-
ment for optical measuring instruments). In 1899 Pulfrich constructed
a stereoscopic range finder, and, after extended studies, devised the
stereocomparator in 1901 ( Zeitschr . f. Instrumentenkunde , 1902).
He also worked with the astronomer M. Wolf, of Heidelberg, in the
field of astronomy, and demonstrated that the mountains and valley of
the moon could be really recognized as such and measured with his
instruments. The development of the stereoscopic measuring method
became of great importance in surveying; he improved the stereocom-
parator and perfected the stereoautograph (automatic measuring
apparatus) invented by E. von Orel. His studies are collected in his
work Die Stereoskopie im Dienste de Photometrie und Pyrometrie
(1923). Professor Dr. E. Dolezal writes: “Pulfrich became the bene-
factor of photogrammetry through his stereocomparator; the method
of stereophotogrammetry originated by him has found a wide-spread
application and the instruments constructed by him for stereophoto-
grammetric use enjoy general favor and esteem.” 8

First Lieutenant E. von Orel, while working in the cartographic

MODERN PHOTOGRAPHIC OPTICS

4°3

division of the Military Geographic Institute, at Vienna, in 1905,
invented the photogrammerric stereoautograph; by its aid contour
lines could be drawn mechanically (automatically). The movements
of the stereocomparators connected with it can be transferred with a
pencil by a pantograph-like line system. His apparatus was constructed
at Jena with the co-operation of Pulfrich. It was then tested in the
Military Geographic Institute, at Vienna, under the supervision of
Lieutenant Field Marshal A. von Hiibl and found widespread use.
This idea was later carried out for the mechanical reproduction of maps
from aerial pictures (see H. Hugersdorff, Autocartograph, by the firm
of Zeiss, at Jena, also Zeitschr. f. Instrumentenkunde, 1931, p. 214).

E. von Orel left Vienna after the collapse of Austria following the
World War and moved to Switzerland, where he follows his vocation.

Chapter LVI. modern photographic
optics

Petzval’s lens met the requirements for portraits perfectly, but his
orthoscope had not a sufficiently large field of view for landscapes and
architectural subjects and was not suitable for reproduction work, be-
cause it was not wholly free from distortion. Many opticians and
photographers experimented with many kinds of new lenses (see
Handbuch, 1911, I (4), “Die photographischen Objektive”).

A new era in lens construction began in 1865 with the calculation
and construction of aplanatic lenses by the ingenious optician Dr.
Adolph Steinheil, of Munich. His activities made Munich for many
years the center for the improvement of photographic lenses.

Dr. A. Steinheil was born at Munich, April 12, 1832, the son of the
celebrated physicist Karl August Steinheil. 1 He studied in Munich and
Augsburg and moved to Vienna in July, 1 850, where his father had
been called for the installation of telegraphy. He continued his studies
in Vienna and was employed, in 1851, as assistant in the telegraph
department of the government.

Adolph Steinheil returned to Munich in November, 1852, and
devoted himself to optics because his father was charged by King
Maximilian II with the task of preserving the reputation of Bavaria
for optical achievement that had been gained by Fraunhofer. During

MODERN PHOTOGRAPHIC OPTICS

404

1853-1855 he took part in the preliminaries for the establishment of the
Optical Institute, which was opened in May, 1855.

His principal work during the next few years consisted in finding
a method of calculations for two image points, one in the optical axis,
the second lying laterally from the axis. During the calculation of the
laterally lying image points it was demonstrated that, in addition to
the pencils of rays outside the optical axis, the rays in the axial plane
must also be calculated. Steinheil the elder requested Professor von
Seidel ( 1 864) to study this problem, and Seidel developed and placed
at their service formulas for the investigation of any rays by a system
of central spherical areas. These figures made it possible to produce an
optical system by calculation alone.

The first photographic lens calculated by Steinheil was the “peris-
cope,” for which he, jointly with his father, took out a patent in 1865.
The Steinheil periscope consisted of two symmetrical single (flint-
glass) menisci of one and the same kind of glass and showed ioo° field
angle free of distortion, but it possessed a different focus. The Stein-
heil wide-angle lens, having been introduced into practice, came to
the notice of the American optician Zentmayer, in Philadelphia, and
he constructed an analogous wide-angle lens with two single flint-glass
menisci of the same kind of glass, but he made the lens unsymmetrical
with a smaller front lens (18 66). The Zentmayer lens, which had to
be diaphragmed down to f/40 when in use, soon disappeared from
the market after Steinheil, in 18 66, brought out his “aplanat,” which,
based on the periscope, was made achromatic.

In the same year Dr. Adolph Steinheil purchased the optical works
and associated with him his elder brother Edward, 2 who looked after
the business affairs. Using the symmetrical periscope as a starting point,
Adolph Steinheil calculated his aplanat, which has become famous;
the construction of this symmetrical, achromatic, and aplanatic double
lens after an original drawing by Dr. Steinheil is reproduced in the
1932 ed. of the Geschichte (p. 566).

On July 26, 1866, Adolph Steinheil sent his first specimen (proof of
which is available) to Monckhoven, in Belgium, who was writing a
book on photographic lenses. Steinheil was granted a patent in Bavaria
on January 14, 1867, for his optical system ( Handbuch , 1884, I, 228).
The first aplanatic lenses had an aperture 1/7 and a angle of view of
60°. This lens was made for landscape and architectural subjects and
groups taken in the open, for which wet collodion plates had sufficient
rapidity.

MODERN PHOTOGRAPHIC OPTICS

405

At the Paris Exposition of 1867 Adolph Steinheil received the gold
medal in the division of optics for correctly drawn constructions
(aplanats, magnifying glasses, oculars, and field-glass lenses) and in the
photographic division, in which the aplanats were passed unnoticed,
a bronze medal for the first wide-angle lens for landscapes. (This lens
was later listed in series V of his price list.)

In 1868 he constructed, on an order from the Military Geographic
Institute, in Vienna, wide-angle lenses for reproduction purposes, with
which cartographic reproductions could be produced without dis-
tortion up to about a square meter (39.37 inches square). He con-
structed wide-angle and landscape aplanats and in 1881 the first
aplanatic lens sets. Steinheil brought examples of this latter construction
to Captain Pizzighelli, who was in charge of the photographic depart-
ment of the Technical Military Committee, in Vienna, where they
were tested. These landscape aplanats had a field of view of 80 0 with
adjustable focus. They were deemed the best of the period, came into
general use, and were quickly imitated by foreign opticians. Follow-
ing long studies on the influence of the thickness of lenses, Steinheil
was granted a patent in 1874 for portrait aplanats and in 1879 for
group aplanats. In 1881 he was granted a patent for antiplanats, after
having made a series of lengthy calculations, disregarding symmetry,
and after having made a partial compensation of the astigmatism.

Adolph Steinheil collaborated with the author in his work on
“Die photographischen Objective,” published in the Handbuch (1884,
Vol. I), and generously supplied the optical data of his lens con-
structions for publication (radii of curvature, qualities of glass) ; these
are the only original construction data of that time for Steinheil
lenses. Adolph Steinheil was on friendly terms with Abbe, who origi-
nally calculated accurately only microscope lenses and joined Steinheil
at Munich in order to learn from him the mathematical calculations
for photographic lenses with large lens apertures as Steinheil executed
them. Abbe found in Steinheil the necessary encouragement. Steinheil
was in no way a secret monger and published, with Professor Ernst
Voigt, of Munich, Handbuch der angewandten Optik (Leipzig, 1891);
however, only one volume appeared. Owing to his protracted labors,
Steinheil lost the sight of one eye, which had to be removed in order
to save the other; he had one artificial eye during the last years of his
life. He died in Munich, Nov. 4, 1893. His son Dr. Rudolf Steinheil
(1865-1930), became the head of the firm after his father’s death and

4 o 6 MODERN PHOTOGRAPHIC OPTICS

introduced new anastigmats. With Dr. Rudolf Steinheil the male
line of this famous family of opticians came to an end. The firm was
changed into a stock company owned by the heirs (five daughters),
and one of Steinheil’s sons-in-law, the engineer L. Franz, became the
manager of the company.

PATENT LITIGATIONS BETWEEN STEINHEIL AND DALLMEYER

A few months after Adolph Steinheil sent to Monckhoven the
first specimen of his aplanats, which in this way became known,
John Henry Dallmeyer, who had emigrated to London from Germany,
came out with an analogous aplanatic constniction. He used flint crown
glass with the flint-glass lens on the outside, instead of Steinheil’s
heavy and light flint glass. Dallmeyer was granted an English patent
(No. 2502) on September 27, 1866, for his “rectilinear.” From this
arose a controversy about the priority rights. Dallmeyer attacked
(Brit. Jour. Phot., 1874, p. 584) the originality of the construction
with weak arguments, but the controversy ended in favor of Steinheil.
He had already, in 1 86 5, published the construction with flint on the
outside in the Nachricbten von der k. Gesellschaft der Wissenschaften
an der Universitat zu Gottingen. (See also Steinheil’s earlier statements
in the Phot. Korr., 1869, p. 97.) Steinheil’s victory over Dallmeyer
was complete from a scientific standpoint, but in a commercial way
he lost, since, owing to the incapacity of his legal representative in
England, Steinheil was deprived of the financial returns from his
invention in that country.

Dallmeyer was connected by marriage with the family of the well-
known optician Ross. The firm of Dallmeyer was founded with the
support of the Ross family and produced not only portrait lenses,
named after Dallmeyer (according to the Petzval system), but also
aplanatic lenses (Steinheil system), which found great favor in
England.

J. H. Dallmeyer died in the early eighties, and his son Thomas Rudolf
Dallmeyer took his place. The old firm of Ross resumed later the com-
mercial production of lenses with renewed vigor and entered actively
into competition. The French opticians also constructed aplanat sets
according to Steinheil’s type: for instance, Frangais in Paris and then
Suterin Switzerland (Handbuch, 1884, Vol. I).

FURTHER APPLICATIONS OF APLANATS

A. Steinheil’s invention of the aplanat was of no less importance for

MODERN PHOTOGRAPHIC OPTICS

407

the photography of architectural subjects, landscapes, interiors, repro-
duction processes, and group pictures than the Petzval lens was for
portrait photography.

The considerable speed of aplanatic lenses and the sharp and correct
delineation to the edges and the lack of stray light due to internal
reflections were their most valuable advantages.

Aplanats of medium rapidity were followed by landscape and wide-
angle aplanats with 8o° to over ioo° angle of view by Steinheil, while
Voigtlander, in Brunswick, constructed according to the aplanatic
system his “euryscope,” which was somewhat faster (1/6) than the
ordinary aplanatic lenses.

Voigtlander brought the first two examples of this lens personally
to Vienna, in 1886, one to the portrait studio of the court photographer
Josef Lowy, another to the author; these lenses were nameless at the
time and were only subsequently called euryscopes. They could be
used with silver bromide gelatine plates for instantaneous exposures
(Eder, Momentphotographie, 2d ed., 1887). Aided by the calculations
of his stepson, Hans Sommer, Voigtlander increased the speed of his
euryscope to such a degree that he relegated the earlier Petzval con-
struction for ordinary portrait lenses to the background and centered
his attention on speed lenses and projection lenses. At the foundation
of the Graphische Lehr- und Versuchsanstalt, at Vienna, Fr. von
Voigtlander presented a valuable collection of all his lenses produced
up to that date. This is the most complete collection of its kind. Voigt-
lander was knighted for this and other services.

INVENTION OF ANASTIGMATS

Aplanatic and similar lenses suffered from the imperfect elimination
of astigmatism on the edges of the picture; Steinheil attempted in 1881
to overcome this defect by antiplanat (with thick glass) along new
lines. The antiplanat was extensively used in the eighties for instanta-
neous and group photography until it was displaced by the anastigmatic
lens. Rudolf Steinheil worked also much later in the modern construc-
tion of lenses. He calculated with Dr. Karl Strehl the orthostigmat
lens of his firm and the quadruple lens combination “unofocal.”

Following Steinheil, the physicist Ernst Abbe devoted himself to
theoretical and applied optics.

Dr. Ernst Abbe (1840-1905) was professor at the university in
Jena, director of the observatory, 1878-1889, joined the optical works
of Carl Zeiss, 1866, became a partner in the firm, 1875, and gave his

4 o8 MODERN PHOTOGRAPHIC OPTICS

share in the business to the Carl Zeiss foundation. He achieved dis-
tinction in the construction of microscopes, field glasses, and photo-
graphic lenses and invented numerous optical apparatus (for his
biography see Ernst Abbe , by Felix Auerbach, 1918; also numerous
publications of Von Rohr; Auerbach also wrote, in 1903, on the Carl
Zeiss Foundation).

Only a very limited number of varieties of glass (“crown and flint”)
were suitable for lens systems in mathematical optics up to the eighties.
In 1884 a glass works was established by Dr. Otto Schott, at Jena,
supported by the German government, which furnished, with Pro-
fessor Abbe’s collaboration, the material for new lens systems. This
Jena glass was produced by the application of new combinations (by
addition of barium, zinc, phosphoric acid, boric acid, and so forth), 3
which permitted the attainment of better achromatism, a more ex-
tended field of view, and other advantages. The introduction of these
new kinds of glass, beginning from 1886 and 1888, stimulated the
production of photographic lenses. Thus A. Steinheil, in 1886, pro-
duced and delivered an aplanat (No. 16147) rnade from special glass;
the firm of Voigtlander & Son, Brunswick, in 1888, made public the
first euryscope (aplanatic type) constructed from special Jena glass.

Professor Abbe called in the clever mathematical optician Dr. Paul
Rudolph (born 18 58), 4 on the results of whose calculations he himself
reported in the Jahrbucb fur Pbotograpbie (1891, p. 225; 1893, p.
221). The first anastigmats, according to Rudolph’s calculations and
produced from the new Jena glass, were patented by the firm of Carl
Zeiss, April 3,1890 (No. 56109). As early as May 30, 1890, the first
examples of the anastigmatic lenses completed by the firm were sent
for tests to the Graphische Lehr- und Versuchsanstalt, Vienna. These
specimens were as follows: a triple lens with the relative opening 1 : 6. 3
and a 90 0 angle of view; an anastigmat 1 : 6.3 with 85° view angle (this
was a double lens system consisting of five lenses); an anastigmat 1:10;
an unsymmetrical double lens system for wide-angle exposures and
for reproductions; and an anastigmat wide angle having 1 10° view
and also a double-lens system consisting of four lenses. All these lenses®
were unsymmetrical, with excellent correction of astigmatism, per-
mitting a great extension of the field of view with uniform sharpness
in every portion of the plate. Dr. Paul Rudolph was justly called the
first inventor of the modern “anastigmat.” After having been granted
the patent of May, 1890, the firm of Carl Zeiss forthwith produced

MODERN PHOTOGRAPHIC OPTICS

409

six series of different relative proportions of apertures— from 1:4.5
up to 1: 18. The anastigmats 1:4.5 up to 1:9 were of the doublet type,
five-lens system; those 1: 12.5 and 1:18 were of the four lens unsym-
metrical type, which Dr. Rudolph illustrated in the author’s Jabrbuch
(1893, p. 226).

The glass used for those lenses was the new Jena glass (Barita flint
and light crown glass). The oldest types of Zeiss lenses were called
“protar” (Eder, Phot. Objektive, 1911, p. 128). In 1895 the double
protars were added to the list (doublets, each of four cemented lenses) .

This modern type of lens construction has been increasingly fol-
lowed since 1890. Later the new construction of tessar lenses (German
patent 142,294, April 25, 1902) made their appearance, the rear lens
consisting of two connected elements and the front lens of two elements
which are separated. They were introduced in different series for
instantaneous and reproduction photography, which chapter of
modern optics we shall not further discuss here.

About 1920 Dr. Rudolph calculated a new six-lens double objective,
in which each two lenses were sealed together and each single lens was
left separate; he called these lenses “doppel-plasmat.” When he found
that the Zeiss works did not show sufficient interest to suit him, he en-
trusted the production of this lens to the optician Hugo Meyer, in
Gorlitz, who had already constructed other lenses (aristostigmat, and
others) . 8

One of the outstanding personalities in the field of modern photo-
graphic optics was Carl Paul Goerz (1856-1930), who succeeded in
working his way up from the most modest beginnings to head of a
gigantic enterprise. 7 After being graduated from the high school,
Goerz became an apprentice in the employ of Emil Busch, at Rathenow.
He worked later in different optical establishments, founding in 1 886
his own business at Berlin, which, as the Goerz optical works, became
well known in every part of the world. He supported the work of
Anschutz and others.

In 1886 he took over a firm dealing in mathematical, drawing imple-
ments, and so forth, which he sold to schools. Recognizing the impor-
tance of photography, he added photographic apparatus to his stock
and began in 1888 to make them in his own shop; in 1890 he joined
Anschutz in the construction of the Goerz- Anschutz cameras for
instantaneous photography, for which he furnished the optical equip-
ment. At first Goerz produced only known types of photographic

MODERN PHOTOGRAPHIC OPTICS

410

lenses; 8 for instance, the triplet landscape lens of Dallmeyer in a some-
what altered form; then, following Steinheil’s aplanats, he successfully
brought out, at the end of the eighties, his “lynkeyoskope.” One day
Goerz received a visit from the mathematical optician E. von Hoegh, 9
at that time wholly unknown, who informed Goerz that he had cal-
culated a new symmetrical lens system, which was very well corrected
anastigmatically. Goerz made tests and recognized with clear fore-
sight the importance of this new construction. He took out a German
patent, in 1893 (No. 74,437) for this symmetrical, anastigmatic,
double lens system, which he named “double-anastigmat” 10 with an
aperture of 1:7.7. Later, finding that the name was not protected by
law and was also used by others, he renamed the lens “Dagor,” and
increased its speed to 1:6.8, producing them with enormous success.

At the World’s Fair in Chicago, Goerz’s double anastigmat attracted
great attention, and the sales increased tremendously. The thirty
thousandth lens of this type was furnished by Goerz in 1896.

The Goerz double anastigmat was patented at once in all countries,
but Goerz forfeited his French patent rights, owing to the error of
having imported one of these lenses into France before the patent was
applied for. When the patent expired in Germany and other countries,
the production of Goerz, Steinheil, and Zeiss lenses became common
property. The Goerz-Hoegh double anastigmat was based on the
symmetrical six-lens reproduction aplanat of Steinheil, but it attained
greater luminosity and better anastigmatism by means of the new Jena
glass used in its production. Dr. Rudolf Steinheil, in Munich, worked
at the same time and independently on a similar construction, but
Goerz-Hoegh had applied for their patent in Germany several weeks
earlier. Steinheil, however, succeeded in getting a patent, but only after
a long dispute with Goerz’s firm on a second type of the six-lens aplanat
with the new Jena glass. This new anastigmat he called “orthostigmat.”
Soon after the publication of the orthostigmat, the firm of Voigtlander
contended that theirs was the prior right to use the Steinheil type,
since they had made all necessary preparations of the invention when
Steinheil applied for his patent, and they compromised by agreeing
that Voigtlander, in Brunswick, would be permitted to manfacture
this lens, which he called “collinear.”

Dr. H. H. Harting calculated the “heliar” of Voigtlander. This lens
was offered for sale in 1902, and the patent was applied for far ahead of
that of the Zeiss tessar, which appeared on the market at the same time

MODERN PHOTOGRAPHIC OPTICS

4i 1

(1902). In the construction of the heliar, magnalium an alloy of mag-
nesium and aluminum, which is much lighter than brass, was used by
Voigtlander for the lens tube. Later the “dynar” and “oxyn” lenses,
calculated by Dr. Harting, were made and sold by Voigtlander.

The optical works of C. P. Goerz at Berlin-Friedenau were very
successful conunercially. They supported scientific investigations in
the various branches of applied optics, and C. P. Goerz was awarded
the honorary degree of Doctor honoris causa. Goerz also established
a factory for the manufacture of gelatine silver bromide films for
cinematography, constructed projectors for photographic projection,
for automobiles, and for military use, and invented carbons with elec-
trolytic deposited copper for electric lamps. In 1925 the firms of
Goerz, Tea, Ernemann, and Contessa-Nettel were consolidated, and
on September 1 5, 1926, they were merged with the firm of Zeiss. The
consolidation was known as Zeiss-Ikon-A.-G. The former Goerz works
in Berlin were continued and carried on under the name of Zeiss-Ikon-
A.-G. Goerz-Werk.

This subject is too broad to be dealt with in further detail here, and
we must confine ourselves to mentioning the old and reputable optical
establishments of Busch, of Rathenow, Meyer, of Gorlitz, Rodenstock,
of Munich, Rietschel Reichert, of Vienna and Suter, of Basel. Dennis
Taylor, in London, calculated the triplet “Cooke lens” which Voigt-
lander improved as the heliar.

In recent years the rapidity of lenses for making the small negatives
of motion pictures has been enormously increased, so that we now
have lenses with apertures of about 1: 1.6 to 1:2, of which details may
be found in the author’s Jahrb. f. Phot.

Reginald S. Clay delivered a lecture on the history of photo-optics
in London, in which he gave due credit to the German scientists and
optical establishments (Opt. Rundsch., 1923, p. 907). Clay arrives at
the most interesting conclusion that most of the better-known lenses
constructed by English opticians were calculated by Germans and
that the Cooke lens of Harold Dennis Taylor (1893) was to be re-
garded as the only really good true English type. The Ross lenses
come from Schroeder; the Ross “homocentric” is the “aristostigmat”
of Meyer, calculated by Kollmorgen; the Ross “telecentric” goes back
to Bielicke; “teleros” comes from Hasselkus, who also calculated the
“Ross-combination” lens. The “aviar,” of Warmisham, produced by
the optical works of Taylor, Taylor and Hobson, is the same as

PHOTOGRAPHIC PHOTOMETRY

412

“dogmar,” but is less efficient; the Ross “xpress” is a poor Zeiss tessar.

For the most recent history of photographic optics, the specialized
literature of the subject should be consulted.

Chapter LVII. further development of

PHOTOCHEMISTRY AND PHOTOGRAPHIC PHO-
TOMETRY

After the publication of the process of daguerreotypy there fol-
lowed an expansion of knowledge of the chemical action of light on
organic substances, due to the fact that in 1839 Jean Baptiste Dumas
produced synthetically trichloracetic acid by the interaction of chlor-
ine on acetic acid in sunlight. This was the beginning of a series of
photosyntheses ( Annal . chim. et phys.; Jour. f. prakt. Chemie, XVII,
202).

In 1848 Anton V. Schrotter (1802-1875), professor of chemistry
at the Vienna Polytechnikum, discovered amorphous red phosphorus
and described it as a new allotropic form of phosphorous. The pri-
ority of his discovery was established by a committee of the Academy
of Science, in Vienna (regardless of the claims of the physician Dr.
Joseph Goldmark, brother of the famous composer Carl Goldmark) .
His bust is placed in the Technical Museum, Vienna.

In the middle of the last century a new era of scientific photochemis-
try began with the investigation on the formation of explosive chlorine
detonating gas under the action of light, by Bunsen and Roscoe. The
starting point of these experiments was a mixture of chlorine gas and
hydrogen; the combination through light action in hydrogen chloride
was known for a long time. J. W. Draper, of New York, had tried
in 1843 to utilize this light reaction for measuring the chemical or
active power of the sunbeam by employing as a photometrical criterion
the diminution of volume which takes place in the formation of
hydrochloric acid when this gas mixture is exposed to light (Draper’s
tithonometer) .

Wittwer, in 1855, commenced his experiments on the decomposi-
tion of chlorine water by light (Poggendorff’s Annal., XCIV, 597)
and calculated the experimental results. They indicated that the decom-
position of chlorine water by light followed the law of mass action of

PHOTOGRAPHIC PHOTOMETRY

4 1 3

Guldberg and Waage. He entered into a controversy with Bunsen and
Roscoe, improved his method in 1858, and continued his research in
1865. His labors received due recognition later from Nernst. This is
gone into more exhaustively in Plotnikow’s Allgemeine Photocbemie
(Berlin and Leipzig, 1920, pp. 96, 133, 369). See also Berthollet’s
(1785) and Saussure’s (1787) earlier work on the sensitivity of chlorine
water to light.

Bunsen and Roscoe, in 1854, entered on investigations of chlorine
detonating gas and recognized that Draper’s tithonometer was not suit-
able for accurate light measurements, due to many basic errors. They
therefore sought a different method of experimentation which would
eliminate these basic faults. After many and tedious attempts, they
succeeded in constructing their chlorine detonating gas photometer,
which enabled them to exclude all disturbing influences from their
measurements. This made it possible to record the chemical action of
light, not only as a relative quantity but also as an absolute measurement.
With these classical investigations on the action of light on chlorine
detonating gas the period of scientific photochemistry was begun.
Their work was the first photochemical measurement and focussed
the attention of scientists on the nature of the reaction producing the
effects of the light rays. Robert Wilhelm Bunsen (1811-1899) col-
laborated at the University of Heidelberg with the English chemist
Henry Enfield Roscoe (1833-1915). The dissertations appeared under
the title, “Photochemische Untersuchungen,” in Poggendorff’s Annal.,

1 85 5-1 859 (reprinted in Ostwald’s , Klassiker der exacten Wissenschaft-
en, pp. 34, 38). They determined the phenomena of induction, deduc-
tion, and extinction. They found that the beginning of light reaction
takes place at first very slowly and that the velocity increases gradually
until it attains a constant value, observing also that steam accelerates
the action and that air retards it. Although this interpretation of the
action of light received later a different theoretical conception, their
investigations were nevertheless epoch-making.

“Photochemical induction” was the name given by Bunsen and
Roscoe to the phenomenon which they first observed in chlorine
detonating gas, namely, that the speed of reaction is slow in the begin-
ning, increases in proportion to the length of exposure, and then
maintains a uniformly steady course.

Bunsen and Roscoe found that within the field in which the so-called

induction disappears the changed quantity of the light-sensitive sub-

PHOTOGRAPHIC PHOTOMETRY

stance (chlorine detonating gas) per time unit is in direct proportion
to the incident light intensity (Bunsen and Roscoe, Reziprozitdts-
Gesetz) }

However one may evaluate the phenomenon of “photochemical
induction” observed first by Bunsen and Roscoe in chlorine detonating
gas, theoretically its importance for practical applied photochemistry
consists in the fact that a certain initial action of light is essential in
order that a normal sequence of the photographic effect may be ob-
tained.

The wet collodion process had already demonstrated that an initial
action of a not-altogether-too-weak light is essential in order to obtain
normal negatives, and this applies also to the gelatine silver bromide
process, which was probably first determined by the author in 1881
(Eder, Die Photo grapbie mit Bromsilbergelatine-Emulsion, 1881; Phot.
Arch., 1881, p. 109).

Bunsen and Roscoe also found that the light absorption by chlorine
in a mixture of chlorine detonating gas was greater than by chlorine
alone. The difference of the absorbed light quantities seems to be taken
up by the chemical energy necessary to the reaction (“ photochemical
light absorption”).

With the aid of the chlorine detonating gas photometer, Bunsen
and Roscoe conducted a series of measurements of the chemical inten-
sity of the direct, as well as of the diffused, sunlight. The determination
of the relationship of the intensity of light to the position of the sun
was established by Bunsen and Roscoe on a clear day (June 6, 1 8 5 8 ) , on
the summit of the Gaisberg, near Heidelberg (375 meters - 1,230
feet). On the basis of the formula given by them, the chemical illumin-
ating power of a clear sky could be calculated for any definite geo-
graphical place at any given time (altitude of the sun). They also found
that the chemical action of the atmosphere’s diffusion of light was
very irregular, particularly when the blue sky was overcast by mist
or clouds. These tables and formulas are the public property of the
photographic world and have served as the basis of all subsequent
exposure tables.

LAW OF PHOTOGRAPHIC RECIPROCITY AND PHOTOMETERS

The first photometer to record photographically was invented by
Landriani.

At the time of daguerreotypy Faustino Jovita Malagutti attempted

PHOTOGRAPHIC PHOTOMETRY

4 X 5

to determine the intensity of daylight by means of the darkening of
silver chloride paper to a certain predetermined standard point; his
object was to measure in this manner the corresponding time of ex-
posure. 2 He accepted in 1839 the hypothetical law of blackening in
which, i • t = constant. Malagutti was born at Bologna, in 1802,
studied in Paris, was Pelouze’s assistant in Gay-Lussac’s laboratory
and later Professor of chemistry at Rennes. He wrote numerous chemi-
cal works and investigated also the law of absorption of ultraviolet rays
(Poggend., Annal., XLIX, 567).

While Malagutti set up the “Law of Reciprocity” in a speculative
manner, he failed to give the precise proofs of his assertions. Bunsen
and Roscoe gave proofs of their theory, and the law is justly named
after them in the later technical literature. Continuing their work
Bunsen and Roscoe in 1862 occupied themselves with the exposure
relationship of silver chloride paper by direct exposure (Poggend.,
Annal., XXVII, 530). They perfected photometry on an exact basis
by the use of photographic silver chloride paper and established experi-
mentally the law of photographic reciprocity, which within certain
limits (see “Die Sensitometrie und photographische Photometrie,” in
Handbuch, 1930, III (4), 13) is valid in this and in the allied methods
for the measurement of the intensity of “chemical rays” at different
times of day and year. All exposure tables in use today by photog-
raphers are based on Bunsen and Roscoe’s measurements. These sub-
jects are fully covered in the different parts of the Handbuch and are
generally known and employed in scientific photography, therefore
we shall not deal with them here in further detail.

Bunsen and Roscoe introduced a standard gray for silver chloride
paper (one part pine soot, 1,000 parts zinc white, and some gelatine).
The number of seconds necessary for the attainment of the standard
gray by silver chloride paper were designated by Bunsen and Roscoe
as the light unit.

It was an auspicious coincidence when three of the leading scientists
of the middle of the last century, Bunsen, Kirchhoff, and Roscoe, met
at the University of Heidelberg.

Robert Wilhelm Bunsen (1811-1899) was called in 1852 from the
University of Breslau to Heidelberg. His outstanding investigations
in the domain of chemistry and physics cannot be discussed in detail
here. Those best known are his investigations in spectrum analysis
which he made jointly with the physicist Gustav Robert Kirchhoff

4 i 6 PHOTOGRAPHIC PHOTOMETRY

(1824-1887), who was called to Heidelberg in 1854. Bunsen and
Kirchhoff laid the foundation for spectrum analysis in i860. Kirch-
hoff went to Berlin in 1875. He was in poor health for years and was
compelled to use crutches for a time. His colleague Bunsen enjoyed
life for many years.

We quote from The Life and Experiences of Sir Henry Enfield
Roscoe (1906, p. 47), written by himself:

Bunsen’s Laboratory was a quaint one. It had been an old monastery. The
high-roofed refectory had been fitted up with work benches, whilst the
chapel became the storeroom. The increasing number of students, how-
ever, made it necessary to enclose the cloisters with glass windows, in
front of which a series of work benches were arranged. . . . Of course,
we had neither water nor gas. We used Berzelius’ spiritlamps, and drew
our water from the pump. All our combustions were of course, made
with charcoal and the evaporation of the wash waters of our analysis was
carried out over charcoal fires.

Notwithstanding this primitive equipment, excellent experimental
work was carried on there by Bunsen and his students. It was not
until 1853 that a new chemical laboratory was built and equipped with
gas, after the demolition of the old monastery.

While Bunsen and Roscoe carried on their experiments on the
photochemistry of chlorine and hydrogen gases, only wooden shutters
in the roof were at their disposal for their observations of the actinism
of the sun rays. Roscoe suffered greatly from the summer heat, but
did not allow this to interfere with his work.

The Englishman Roscoe was graduated from the University of Lon-
don, 1835, with the degree of Bachelor of Arts. He went to Heidelberg
in the same year for a postgraduate course in chemistry with Bunsen,
who soon made him an assistant in his scientific work. They began in
1854 their investigations of the chemical action of light on a mixture
of chlorine and hydrogen as mentioned above. Roscoe received his
doctorate in Leipzig and became in 1857 professor of chemistry at the
University of Manchester. He often returned to his beloved teacher
Bunsen, and he spent his summer vacations in Heidelberg until 1863,
when he married. The most important results of their joint work are
their photochemical investigations. Later Roscoe worked indepen-
dently and published, in 1865, the Method of Meteorological Registra-
tion of the Chemical Action of the Total Daylight, in which he recom-
mended employing silver chloride paper; further dissertations on this

PHOTOGRAPHIC PHOTOMETRY

subject followed in 1870; most of them are published in the Philoso-
phical Transactions.

Julius von Wiesner (1838-1916), professor at the University of
Vienna, employed the Bunsen silver chloride paper photometer in his
extensive light measurements in botany, plant physiology, and meteor-
ology (1893-1906). This method of measurement, however, furnishes
only qualitative results of relatively short exposures.

A new era in photographic photometry commenced with the intro-
duction of step wedge photometers. The first idea of the use of several
layers of thin paper for testing chemical light intensities was that
proposed by Senebier in 1782, but his experiments were extremely
primitive (see Chapter XIII).

The modern paper-scale photometer, by gradations of transparent
strips of paper, was introduced by Lanet de Limenci, 1856. It was in-
tended at first for visual observation of the intensity of illumination.
When this instrument was presented to the Paris Photographic Society,
February 15, 1856, the chemist Henri Victor Regnault pointed out
that the photographic and the visual degrees of luminosity are not
identical, but that one could place a piece of silver chloride paper
behind the scale and thus measure the chemical intensity of the light
( Handbuch , 1930, III (4) , “Sensitometrie,” p. 3). This photometer
was very widely used in photographic printing with pigments, es-
pecially in the form given it by H. W. Vogel.

The standard color photometer, with sporadic light measurements
at certain times of day, yielded no accurate average of the total radia-
tion during a day, which is important in the study of botany and the
cultivation of plants. This induced the Benedictine monk Benedict
John Kissling, at Gottweig on the Danube (Lower Austria), to study
the connection between a continuous light measurement and vegeta-
tion. Kissling was born in 1851, studied at Krems at the same time
as the author, entered his novitiate in 1872, became a priest in 1877, and
died in 1926.

Kissling specialized in botany and studied especially the connection
between vegetation and meteorological conditions and the prevailing
light intensity. He took into consideration for his purpose, the de-
termination of the total volume of light on a certain day. Kissling chose
for his measurements, on the author’s advice, a calibrated Vogel paper-
scale photometer with potassium monochromate paper (dipped in 5
percent solution), which is more suitable for protracted measurements

PHOTOGRAPHIC PHOTOMETRY

418

than silver chloride paper, owing to its slight sensitivity. Graduated
ground glass was also used for the softening of the light. These photom-
eter degrees he reduced to Bunsen light units, and he carried out
numerous measurements. Kissling must be regarded as the first to in-
troduce into botany exact continuous light measurement within the
limits of error of the method . 3

In 1895 he collected his observations, covering many years, in his
pamphlet Beitrdge zur Kenntnis des Einflusses der chemischen Licht-
intensitdt auf die Vegetation.

The light-sensitivity of a mixture of a solution of mercury chloride
with ammonium-oxalate (separation of a precipitate of mercurous
chloride) for photometric use was proposed by Fowler in 1858; he
failed, however, to take into consideration the influence of the concen-
tration and temperature. Eder’s investigations in this field produced the
“mercury-oxalate-photometer” (reported to the Academy of Science,
Vienna, October, 1879); he recognized that it possessed the dominant
sensitivity in the ultraviolet; he also determined the course of the
reaction.

With this mixture of mercury chloride and ammonium-oxalate of
a fixed concentration, called briefly “Eder’s photometric solution,”
many experiments were undertaken.

It is worthy of notice that the author determined for the first time
in 1879 the so-called photochemical coefficient of temperature, in his
dissertation mentioned above, which he found to be 1.19. 4

He was also the first to determine that for silver bromide gelatine
plates differences in temperature from 5 0 to 25 0 C. have no influence
on the formation of the latent photographic image, which means that
the coefficient of temperature equals 1 or lies very near 1 , which was
confirmed by subsequent investigations ( Sitzungsberichte , Akad. d.
Wiss. in Wien, Abt. 11 , April 8, 1880, Vol. LXXXI) .

BASIC LAWS OF PHOTOCHEMISTRY

The Faraday Society of London invited to Oxford for October
1 and 2, 1924, photochemists of all countries for a debate on the photo-
chemical law of Einstein and the properties of light reactions in general.
In Camera (1925, IV, 1 14) Dr. J. Plotnikow prints the report which
he rendered at this congress. In this lecture he treated the question
which photochemical practices must be considered as fundamental
laws. One hundred years ago Theodore Grotthuss (1817) declared

PHOTOGRAPHIC PHOTOMETRY

419

that only the light absorbed by a substance can act photochemically,
and since that time until today we know of no case where this rule did
not operate. A phenomenon or a rule of such an inclusive character
must be called a basic law. There also exists a quantitative relation
between the transformed amount of material and the absorbed light
energy. If we designate the speed of the light reaction (that is, the
amount of material transformed per time unit) as v and the absorbed
light energy as A, we arrive at the general equation v = F (A). This
formula is of a general character and says not a thing about the func-
tion, F. Van’t Hoff expressed the idea (1904) that there must exist here
a simple linear proportionality, that is, that the quantitative expression
of Grotthuss’s law must have the following form: v = kA, in which k
represents the constant chemical speed of the individual light reaction.
The direct examination, as well as a series of consequences which re-
sult from this formula, confirmed its correctness. We can justly accept
it as a quantitative extension of the original law and combine them as
the Grotthuss- Van’t Hoff photochemical law of absorption. The revo-
lutionary changes which physics has undergone in the last decades
could not remain withoutinfluence upon photochemistry, which is on a
borderline between physics and chemistry. In the nineties Lenard and
Hallwachs discovered and investigated the photoelectric phenomena.
It developed the fact that the energy of motion of electrons ejected by
light is related to the frequency of vibration of the light waves. In 1 900
Professor Max Planck demonstrated that the absorption and emission
of light, which is of a photoelectric nature, takes place in so-called
quanta (in numerous minute quantities of energy).

Professor Albert Einstein, born March 14, 1879, applied ( 1905-191 2 )
Planck’s quantum theory to the absorption of light and to the photo-
chemical reaction resulting from it in order to create a basis for the
system of the quantitative course of chemical light actions. He formu-
later this in the so-called “Einstein’s photochemical principle of equiva-
lence,” Q = Nhv. This refers to the absorbed energy, Q, the vibration
frequency of the absorbed light, v, the quantum of energy, h, to the
molecules split by the light, N. In the direct application of this formula
to photochemical reaction difficulties were encountered. Numerous
scientists, such as E. Warburg, W. Nernst, M. Bodenstein, F. Weigert,
J. Stark, and others, worked on the further extension and adaptation of
Einstein’s law and continued experiments and observations.

In the light of the recent physicochemical conception, the reaction

SELENIUM

420

which takes place in the formation of a photographic image consists in
the transfer of an electron from a brom ion to a silver ion ( Handbuch ,
1927, I (1), 633-35). O n the relation to the quantum theory, S. E.
Sheppard reported to the Seventh International Congress of Photog-
raphy, at Dresden, in 1931. On electrons, atoms, and light quanta and
the historical development of the respective theories see Arthur Haas,
Atomtheorie (1929).

Chapter LVIII. photoelectric properties

OF SELENIUM

Recent experiments for transmission of the photographic image
were directed to the construction of telegraphic printing apparatus
and the like, where one or more light-sensitive cells are installed at the
receiving end. This apparatus was based on the change of electrical
resistance, on photoelectricity and on radiophone action. The his-
torical development was described by R. Ed. Liesegang, in his Beitrd-
ge zum Problem des elektrischen Fernsehens (1899). We will here
merely relate the curious behavior of selenium toward light. Of par-
ticular interest is the discovery of the influence of light on the electrical
conductivity of selenium and other substances, which made possible
television. The transmission of an optical lens image over long dis-
tances was anticipated by Goethe in the tenth canto of his Reinecke
Fuchs. “Hear now further of the mirror, in which the glass is replaced
by a beryl of great clearness and beauty; everything in it is reproduced,
even if happening miles away, be it day or night.” This dream of
Goethe’s came true in the nineteenth century through the finding of
selenium.

Selenium was discovered by Berzelius in 1817. It exists in several al-
lotropic forms, namely, as glassy or amorphous and as crystalline se-
lenium. It occurs as an amorphous reddish powder and also in shiny
thin sheets, which are transparent red. When heated, it forms the
crystalline black selenium which possesses a mat, metallic surface re-
sembling lead.

The German physicist J. W. Hittorf 1 (1851) demonstrated that
the metallic form exhibits a curious behavior toward the electric cur-
rent and conducts electricity. He also observed that sunlight had a
great influence on the transformation of the amorphous, hydrous se-

GELATINE SILVER BROMIDE

421

lenium precipitated from an aqueous solution into the crystalline
metallic form. Hittorf, however, considered selenium insensitive to
light, but credited the change which red selenium undergoes from the
rays of the sun to the temperature.

Willoughby Smith utilized selenium in 1873 on account of its high
resistance in a method for measuring and signaling during the laying
of a submarine cable. Experiments proved that selenium offers the re-
quired resistance in full measure; a resistance equal to that of a telegraph
wire reaching from the earth to the sun. Since it was found, however,
that the resistance was extraordinarily variable, it became necessary to
make tests in order to ascertain the cause of this variability. During
this test, May, an assistant to Willoughby Smith, discovered that the
resistance of selenium was less when it was exposed to light than in
the dark. 2

Thus he found that light influences electric conductivity and that
modern electrotechnology, for instance, the telephone, could be served
by the action of light. The first successful tests of this kind moved
Smith, in 1 87 3, to the following enthusiastic expression.

Mr. Preece related to us that with the aid of the microphone the running
of a fly could be heard so loud that it resembled the trampling of a horse
on a wooden bridge, but I can tell you a story which I think is still more
wonderful, namely, that I heard with the aid of a telephone a ray of light
fall on a metal plate.

Werner Siemens 3 found that there are certain forms of selenium
which are so extremely sensitive to light that quite minute light inten-
sities were sufficient to increase considerably the conductivity of se-
lenium for the electric current. In more recent times very sensitive
selenium cells were constructed which were very suitable for pho-
tometry, electric transmission of light effects, photophones, and the
recording of sound films. 4

Chapter LIX. gelatine silver bromide

Poitevin’s experiments (1850) to utilize gelatine as a binding agent
for silver salts in the negative process were not wholly successful.
Years passed before the idea, proposed by Gaudin in 1 85 3, of producing
emulsions with different binding agents, among others with gelatine,
was realized. First it had to be learned that silver 'bromide (not silver

GELATINE SILVER BROMIDE

422

iodide) must form the principal part of such emulsions and, further-
more, that the great light-sensitivity of silver bromide becomes effec-
tive only by chemical processes of development, for instance, with
alkaline pyrogallol. Only when this was known did the use of gelatine
(in place of collodion) as a colloid medium in the emulsification of
silver bromide meet with complete success. But this vital perception
was gained only after many experiments had failed.

The Englishman W. H. Harrison published (Brit. Jour. Pbot.,
January 17, 1868), in a short article entitled “The Philosophy of Dry
Plates,” an account of his half successful experiments with silver bromo-
iodide (with use of cadmium iodide and cadmium bromide), which
he emulsified in a very weak gelatine solution. He coated plates with
this emulsion, which he dried, exposed, and developed with pyro-
gallol. He remarked that the image appeared quickly and was of great
intensity, but it was useless, owing to the rough and uneven surface
of the film. He attempted to improve his emulsion by increasing the
gelatine content, but then failed to obtain an image, proof that his
experimentation was faulty. Apparently discouraged, he discontinued
further trials with gelatine emulsion after the publication of his failure.
In these circumstances he can hardly, claim consideration as a pioneer,
still less the inventor of gelatine silver bromide emulsions.

W. Jerome Harrison mentions, with great accuracy, in his History
of Photography ( 1 888, p. 59) these unsuccessful fledgling experiments
by W. H. Harrison with gelatine silver bromo-iodide. He can be called,
therefore, only an experimenter who stopped after his initial attempt.

The experiments of W. H. Harrison so discouraged all other photo-
graphic experimenters that for the five years following no one took up
the use of gelatine as a binding agent for silver bromide; then Dr. R. L.
Maddox independently succeeded in obtaining the first satisfactory
images on gelatine silver bromide, which resulted in further progress.
This English amateur photographer must be recognized as the inventor
of the first serviceable gelatine silver bromide emulsion. 1 Richard L.
Maddox (1816-1902) studied medicine in England, followed his pro-
fession for several years in Constantinople, and married there in 1 849.
In 1875 he practiced in Ajaccio (Corsica) and in Bordighera (Italy),
and later he returned to England. He devoted himself to photography
as early as the fifties and received medals for his microphbtographs in
1853 from the Photographic Society of London and in 1865 at the
Dublin International Exhibition. While practicing medicine in Eng-

GELATINE SILVER BROMIDE

423

land, Maddox worked diligently as an amateur photographer. He
worked a great deal with albumen films on glass plates, Niepceotypy
(Brit. Jour. Phot., VIII, 386); also Kreutzer’s Zeitschr. Phot., 1862,
V, 58). The editor of the British Journal of Photography was his
friend, and he wrote other articles on photographic subjects for this
periodical. His most important contribution, however, was the success-
ful experiment with gelatine silver bromide emulsion.

On September 8, 1871, Maddox sent the first notice on the prepara-
tion of gelatine silver bromide emulsion to the British Journal of Photo-
graphy, under the title “An experiment with Gelatine-Bromide,” and
at the same time handed to Taylor, the editor of the Journal, some
negatives of landscapes, views and so forth produced by the new
process, representing the first successful photographs made with gela-
tine silver bromide dry plates.

Dr. Maddox, in the course of his experiments, was influenced by the
Niepceotype process and the wet collodion process, to which he had
become accustomed in his younger years, and so started with the
physical development (nitrate of silver and pyrogallol) of his gelatine
silver bromide plates, thus permitting the silver nitrate to predominate.
His modesty caused him to use the expression that he “did not assume
to have proposed something new,” when he replaced collodion by
another binding agent, namely, gelatine, though in fact it introduced
a new epoch in photography. He found that the suitable, relatively
great concentration of the gelatine solution, which produced smooth
films on glass as well as on paper, did no injury to the silver bromide
layer in drying.

It is very characteristic in the evaluation of this scientist, as he
himself stated, that his investigations were by no means concluded,
but that he made them public to point the way, as he did in a most
admirable manner, and that they ought to be followed by the further
elaboration of the gelatine emulsion process. He advised the study of
the proportion of bromide to silver nitrate, of the kinds of soluble
bromide which could replace the cadmium bromide which he had
used, and he recommended also the study of the kind of developer.
It is therefore established without doubt that Maddox invented and
documented with good proofs photography with gelatine silver bro-
mide on glass as applied to negative and positive processes, as well as
gelatine silver bromide papers in their initial stages.

He states at the end of his communication to the British Journal of

GELATINE SILVER BROMIDE

424

Photography, 1871: “as far as may be judged at present, the process
seems worthy of further and carefully carried out experiments; if
found advantageous, progress in photography will be promoted by
it.”

Certainly he did not realize that the bromide should predominate
when mixed with silver nitrate and that it was necessary to wash the
emulsion in order to obtain more sensitive and more permanent silver
bromide plates, a fact which was published only in 1873 by J. Johnston.

The famous negatives sent by Maddox in 1871 to Taylor for his
examination were later sent to the present author in the eighties. They
were small, delicate, completely detailed brown negatives. Later, in
1900, I received from Maddox a portrait made about that time which
is reproduced in the 1932 German edition of the History (p. 591).

Dr. Maddox derived no pecuniary returns from his invention and
passed his last years in anything but easy circumstances. In 1892 the
photographers in England, France, Germany, and America and ama-
teurs subscribed for him a sum of over five hundred pounds. In
recognition of the value of his work, he earned the grateful appre-
ciation of his professional colleagues, which was expressed in particular
in the presentation of the “Progress Medal” of the Royal Photographic
Society in 1901. 2 Dr. Maddox died May n, 1902, at Southampton,
in his eighty-sixth year. 3 It was not until two years later that Maddox’s
invention was taken up again and improved by others.

The Englishman J. Burgess, in July, 1 87 3, offered for sale in London
the first gelatine emulsion; it was advertised in the British Journal of
Photography (July 18, 1873). Burgess never disclosed his formula for
this emulsion, but he undoubtedly used the soluble bromide in excess in
preparing the emulsion, since he used an alkaline pyro developer. To
him is due the merit of having been the first actually to produce gelatine
emulsions in a practical and suitable quality for the trade. This emul-
sion was, of course, hardly as sensitive as a wet collodion plate, but
even this was a great deal at that time. Burgess, however, achieved no
commercial success, and the emulsion itself gradually dropped out
of the market.

J. King, on November 14, 1873, gave a more detailed description of
the gelatine emulsion process (Brit. Jour. Phot., 1873, p. 342, and 1874,
p. 294; Phot. Korr., 1874, p. 125), and he introduced the washing out
of the soluble salts from the gelatine emulsion. In the same issue of the
British Journal of Photography J. Johnston recommended the use of

GELATINE SILVER BROMIDE

4*5

soluble bromide in excess in the emulsion mixture and the washing of
the gelatine emulsion. This improvement, that the bromide must be in
excess of the silver nitrate, was recognized later as highly important
and adopted as a rule for the preparation of gelatine emulsions.

As early as 1873 an anonymous writer, who only signed himself
“Contributor,” in the British Journal of Photography (1873, p. 73),
reported that a gelatine silver bromide emulsion could be prepared by
dissolving precipitated and washed silver oxide or silver carbonate in
ammonia and mixing it with a gelatine solution containing ammonium
bromide, but no attention was paid to this vague remark about the use
of ammonia.

Richard Kennett, an amateur photographer in London, on Novem-
ber 20, 1 873, took out an English patent (No. 3782) on the preparation
of stable “sensitive pellicles” (foils) of dried gelatine silver bromide,
which were commercially used for a short time. After being softened
in water and melted, this dried gelatine silver bromide served for
coating glass plates (Brit. Jour. Phot., 1874, p. 291). He also sold
ready-made gelatine silver bromide plates on glass in 1874 on a small
scale for special orders; but they contained silver bromide of poor
sensitivity.

In 1873 W. B. Bolton made public his method, which consisted in
emulsifying the silver bromide at first with very small amounts of
gelatine and later adding more gelatine, a procedure which was sub-
sequently recognized as especially important.

In 1874 Peter Mawdsley mentioned in the Year-Book of Photog-
raphy (pp. 115-116 of that year) the applicability of gelatine silver
bromide paper, with development for the production of negative and
positive prints, and founded the Liverpool Dry-Plate and Photographic
Printing Company. It was the first establishment to produce gelatine
dry plates and photographic papers in fairly large quantities for com-
mercial use; but the business did not meet with success.

J. Johnston described, in 1877, the use of ammonia for ripening
gelatine silver bromide emulsions (Brit. Jour. Phot. Almanac, 1877,
p. 95), a process which later was investigated more closely and per-
fected by Monckhoven. In the middle seventies gelatine silver bromide
plates, which at that time were not very rapid, equaling in sensitivity
only a wet collodion plate, were used in England experimentally for
landscapes and here and there by itinerant photographers for portraits.

In 1877 the world’s attention was directed to dry plates by Pope

GELATINE SILVER BROMIDE

426

Leo XIII. One of the first practical accomplishments of the gelatine
silver bromide photography was the taking of a photograph of Pope
Leo and his entourage in the Vatican garden at Rome on such a plate,
with an exposure of one second. The picture was so satisfactory to the
Holy Father that he paid it the distinction of expressing his pleasure in
the following Latin poem, which he sent to Princess Isabella of Ba-
varia.* It reads:

Ars Photographica
Expressa solis speculo
Nitens imago, quam bene
Fronds decus, vim luminum
Refert et oris gratiam!

O mira virtus ingenii!

Novumque monstrum! imaginem
Naturae Apelles aemulus
Non pulchriorem pingeret.

It may be translated as follows:

The Art of Photography
Breathed on by the mirror of the sun,

A brilliant image appears

How beautifully it reflects the forehead,

The light of the eye, the charm of the mouth.

Oh marvelous power of the mind,

Nature’s new creation

Not even the hand of Appeles, the Master,

Could have produced it more effectively.

In the meantime the chemical processes involved in the production
of gelatine silver bromide emulsions and the means for increasing their
sensitivity were studied more closely.

As a fundamental observation on the possibility of increasing the
sensitivity of gelatine silver bromide, Charles Bennet published, on
March 29, 1878, in his article “A Sensitive Process,” in the British
Journal of Photography (1878, p. 146; 1879, p. 133; Phot. Jour., 1879,
p. 68; Phot. Korr., 1878, p. 21, and 1879, p. 86) that gelatine silver
bromide greatly gains in sensitivity when it is prepared with an excess
of potassium bromide and heated for a long time (five to ten days) at
32 0 C. Certainly the gelatine underwent a partial change, or it fer-
mented and lost its firmness, but it was improved, according to the

GELATINE SILVER BROMIDE

4 2 7

procedure, earlier demonstrated by Bolton, of reserving a part of the
gelatine and adding fresh gelatine at the end of the “ripening process
of the silver bromide.” Thus a method was provided for the com-
mercial production of dry plates, although the sensitiveness of the first
examples offered for sale was still far behind our modern rapid plates.
The road was opened to portrait photography and also to landscape
and instantaneous photography. This ripening by heat was subsequent-
ly varied, by permitting the action to take several hours at 60° to 80°
C. or a half hour at near the boiling point, but the principle remained
the same.

It was not easy to prepare gelatine silver bromide emulsion in the
primitive darkroom laboratories of the professional photographer,
equipped as they were at that time for the still-prevailing wet collodion
process, and every effort was exerted to produce a large number of dry
plates on a commercial scale, keep them in stock, and introduce them on
the market ready for use. This brought about the commercial manu-
facture of sensitive dry plates, which originated in England, as did the
entire gelatine silver bromide process.

The firm of Wratten and Wainwright 5 put on the market in London
in April, 1878, gelatine silver bromide plates of greater sensitivity; this
firm did an extensive export business to the continent, and their plates
were the first to be used in Vienna, through the agency of the Vienna
Photographic Society under the presidency of Dr. E. Hornig, and
later in Berlin.

The “Liverpool Dry-Plate Co.” (Peter Mawdsley) produced in
the same year plates of even greater sensitivity, which they called
“Bennet plates” and sold at three shillings a dozen (size about 3 % X
4% inches).

In 1879 the English firm of Mawson and Swan entered the field with
gelatine silver bromide plates (Sir Joseph W. Swan was formerly a
manufacturer of pigment papers) . The firm was the first to manufac-
ture, in addition to portrait and landscape plates, “photomechanical
plates” for the reproduction processes and to prescribe their develop-
ment with hydroquinone and caustic potash (about 1890), which is
still used today.

In 1879 the Belgian chemist and photographer Dr. van Monckhoven
devoted himself to the development of the dry-plate manufacture.

Van Monckhoven, in August, 1 879,® stated that the increase in sensi-
tivity of the silver bromide emulsion under continued digestion was

GELATINE SILVER BROMIDE

428

connected with molecular changes. 7 He cited on this occasion the
earlier statement of Stas (1874) on the various modifications of silver
bromide 8 and made the far-reaching discovery that the ripening of
silver bromide was greatly accelerated by ammonia.

Supplementing this, Monckhoven published in the Photographiscbes
Archiv (1879) an ingenious emulsion process which did away with
the washing of the emulsion. The silver was precipitated as carbonate
of silver, washed and mixed with a gelatine solution and converted by
the aid of hydrobromic acid into silver bromide. This process, though
practical, was not generally adopted, and Monckhoven himself emul-
sified later in the usual manner with excess of potassium bromide, but
ripened the emulsion with ammonia, in order to obtain a greater sen-
sitivity, and afterwards washed as was then the general custom. Further
details of the method he used are not known, because he kept it secret.
He and his sister-in-law produced the gelatine silver bromide emulsions
for the trade in his laboratory at Ghent.

Monckhoven prepared only the emulsion and sold his product to
two plate factories, namely, Bernaert, in Ghent, and Palmer Descamps
in Courtrai, for use in coating the plates. He used in the early eighties
120 kg. (about 264.6 lbs.) of silver nitrate monthly, which he bought
in Frankfurt a. M. Bernaert coated daily 1,300 plates (on Belgian
glass) ; some of these plates found daily use, about 1880, in the portrait
studio of the court photographer, Jos. Lowy, of Vienna. It was there
that the author familiarized himself with these plates and found their
sensitivity about 20° to 30° on the Warnerke sensitometer (which is
equal to 8°-io° on the Scheiner). These Monckhoven-Bernaert plates
became great favorites, owing to their clearness, fine rendering of the
middle tones, and brilliancy, but the more sensitive English product
replaced them later.

Dr. Desire Charles Emanuel van Monckhoven (1834-1882) was
one of the most versatile and zealous representatives of scientific and
applied photography in the latter half of the last century. He came
from the Flemish race and spoke German fluently, although his daily
conversation was carried on in French. He studied chemistry, did not
engage in a business or profession, lived at Ghent, and devoted himself
early in life to photographic studies. In his eighteenth year he published
his Traite general de photo grapbie, of which seven editions were pub-
lished and which was translated into French, German, Italian, and
Russian. His other well-known publication was Traite populaire de

GELATINE SILVER BROMIDE

429

photographie sur collodion (Paris, 1862). Of importance were his in-
troduction of the dialytic enlarger and an improvement of Woodward’s
solar camera for enlarging, in 1864, as well as his appliances for the
improvement of artificial illumination which he made known in 1869.
He spent also a great deal of time in the study of photographic optics.
His Photographiscbe Optik was published at Vienna, in 1866, and an
English translation, in 1867. He erected in Belgium an establishment
for the manufacture of pigment papers, which contributed greatly to
the spread of this process.

In 1867 he moved to Vienna and aided the portrait photographer
Rabending (inventor of negative retouching) in establishing an impos-
ing studio, which excited great curiosity at the time on account of
its peculiar construction (large broad front light, with small side light) ,
which, while it realized all expectations as far as optical considerations
were concerned, permitting short exposures, did not fully meet artistic
requirements. Although he was quite happy in the gay Viennese life,
he returned to Ghent in the autumn of 1 870. The medal bestowed upon
him by the Vienna Photographic Society in 1871 had to be sent to him
there.

In 1879 he erected at Ghent a completely equipped laboratory, in
which he carried on later his famous experiments in the ripening of
gelatine silver bromide and so forth. Instruction sur le procede au
gelatino-bromure d' argent (1879) and Du gelatino-bromure d' argent
(1880) appeared at this time.

We have already reported above on the emulsion factory established
by him. In this laboratory, as a hobby, he made spectral analyses for
the investigation of the sensitivity of plates, photographed the spec-
trum of hydrogen in special vacuum tubes, which had to be used
longitudinally and were named after him, occupied himself a great
deal with astronomy, and had an observatory in his own house at the
Rue de l’Hopital in Ghent, which was purchased by the government
after his death.

The ammoniacal ripening method of Monckhoven was further
developed by the author, whose investigations in 1880 resulted in the
method of ammoniacal silver oxide and its introduction to emulsion
practice. The author also made public in the same year the favorable
influence of ammonia and ammonium carbonate on the ripening of
emulsion in the cold. The ammoniacal method is used at present for
different kinds of emulsions. For extra rapid emulsion, the neutral boiled

GELATINE SILVER BROMIDE

430

emulsion, with a very small gelatine content, became of great impor-
tance during the process of ripening. It consisted in treating the silver
bromide mixture with very weak gelatine solutions, then allowing it
to ripen for half an hour at about 90° C., and only then adding the
larger amount, left over, of the gelatine solution. The proportion of
bromide to silver nitrate is important, and only a small excess of soluble
bromide occurs in this process. The impetus to this improved method
was given by the investigations of William de Wiveleslie Abney,
Burton, and others ( Handbuch , 1927, II(i), by Liippo-Cramer, and
11(2), by Eder).

Soon the number of factories, at first limited, increased in all coun-
tries, and as early as the eighteen-eighties highly efficient dry-plate
factories sprang up which developed into an industry in which millions
were invested.

At this time (about 1880) wet collodion plates disappeared almost
completely from the portrait and landscape studios and were used only
in photomechanical establishments.

We mention some of the earliest technical literature on gelatine
silver bromide: Abney, E?nulsion Processes in Photography (London,
1878); Abney, The Practical Working of the Gelatine Emulsion
Process ( London , 1880); Burgess, The Argentic Gelatino-Bromide
Worker's Guide (Greenwich, 1880); Chardon, Photographie par
emulsion sensible; bromure d' argent et gelatine (Paris, 1880); and
Monckhoven, Instruction sur le procede au gelatino-bromure d' argent

( l %79)-

The first German textbook on the preparation of gelatine silver
bromide emulsions based on original investigations appeared in January,
1881, written by the author, Theorie und Praxis der Photographie
mit Bromsilber gelatine.

The author’s experiments for the preparation of ammoniacal gelatine
silver bromide emulsions were connected with Monckhoven’s studies
(addition of ammonia to the mixed emulsion). He collaborated at that
time with Captain Giuseppe Pizzighelli, in Vienna, began the tests in
1880 for the preparation of emulsions with the use of ammoniacal silver
nitrate, investigated accurately its modes of use, unknown at that time,
with regard to the proper proportions of the mixture and its tempera-
ture, and summarized the detailed results in his dissertation “Beitrage
zur Photochemic des Bromsilbers ( Sitzungberichte , Akadem. d. Wis-

GELATINE SILVER BROMIDE

43i

sensch., Wien, April 8, 1 880, LXXXI, 679, also Phot. Korr., June, 1880,
p. 144), and in his monograph mentioned above. In the same year
appeared an enlarged English edition of that book: Modern Dry Plates;
or, Emulsion Photography, ed. by H. B. Pritchard (London, 1881),
and later a French edition (Paris, 1883). These directions for the work
with ammoniacal silver nitrate, through the mild digestion temperature
and the rapid working, produced clear and strong gelatine silver bro-
mide plates and opened the way for the commercial production of
emulsions. They were used by almost all the older factories in Germany
and Austria, for instance, by Haack, 9 Dr. Heid, Schattera in Vienna,
Schleussner in Frankfurt a.M., and others. They harmonized well with
the new iron oxalate developer which came into vogue at that time,
as well as with the alkaline pyro developers which had replaced the
ammoniacal pyro developer. The “hard” brands of gelatine, especially
suited for this process, were first successfully produced on advice of
the author in 1881 by the gelatine factory of Winterthur, which was
directed at that time by Simeons. 10

The industrial development of the manufacture of dry plates had its
beginning in England. From April, 1878, a large volume of dry plates
were exported by Wratten and Wainwright, London, the Liverpool
Dry-Plate Co., Mawson and Swan, and others. In Holland, Wegner
and Mottu made dry plates for portraiture in 1877 and 1878 which
were sold by Schippang in Berlin from January 1878. Their sensi-
tivity was four times greater than that of the wet collodion plate
(Wilh. Dost, Phot. Chronik, 1928, p. 376).

In Austria (Vienna) Carl Haack was the first to produce gelatine
silver bromide plates and offer them for sale, October, 1879 (Phot.
Korr., 1879, p. 193) - 11

In Vienna the chemist Dr. Heid started, in 1880, a dry-plate factory;
later followed Victor Angerer and Dr. Szekely. Lowy and Plener, in
1884, were the first to employ contrifuged silver bromide from ripe
gelatine emulsions, and they were also the first to produce and to
employ in Lowy’s graphic art and reproduction establishment the
orthochromatic gelatine silver bromide emulsions with erythrosin ac-
cording to the author’s directions. Later Schattera started under the
direction of Perlmann a dry-plate factory in Vienna, which merged
with the factory run by Ferdinand Hrdlicka 12 under the name “Her-
lango,” which joined the dry-plate factory of Professor Alex. Lainer.

GELATINE SILVER BROMIDE

43 *

In Germany the firm of John Sachs & Co. erected in March, 1 879,
the first dry-plate factory in Berlin under the firm name Glaserei fur
photographische Trockenplatten. This firm coated the plates with
emulsion by machinery. Its first advertisement appeared July 29, 1880,
in the Photographisches W ochenblatt. These plates were four times
more sensitive than wet plates. The production of gelatine dry plates
was begun in November, 1879, by F. Wilde, at Gorlitz; in 1884 by
Dr. Schleussner, at Frankfurt a. M.; later by Hauff, at Feuerbach, 13
John Herzog at Hemelingen, near Bremen (1888), and others. In
1893 the company, Allgemeine Gesellschaft fur Anilin Fabrikation,
at Berlin (later called “Agfa”) introduced the manufacture of dry
plates under the direction of the chemist Dr. Andresen, from which
developed gradually this firm’s great factories for the production of
dry plates and later of films at Wolfen.

The manufacture of dry plates in the United States is closely inter-
woven with the name of George Eastman; Eastman offered his gelatine
silver bromide plates for sale in 1880, as described in detail in Chapter
LXIV. In France silver bromide plates were produced very early; the
most important firm in this line was that of Lumiere.

The manufacture of dry plates was started in 1882 by Antoine
Lumiere, at Lyon, with a daily output of sixty dozen plates. The firm
later grew considerably, under the co-operation and direction of his
sons, Auguste and Louis Lumiere, and achieved a triumph in photo-
chemical practice in 1907 through the invention of autochrome plates.

The entire recent development of the dry-plate industry is described
by Dr. Wentzel in the Handbuch (1930, Vol. Ill, Part 1).

DEVELOPER FOR GELATINE SILVER BROMIDES

Chemical developers (such as pyrogallol solution) proved at an early
stage more advantageous for silver collodion emulsion as well as gela-
tine silver bromide plates than the physical developers of the old wet
collodion process.

At first the gelatine silver bromide dry plates which came on the
market were developed exclusively with pyro-ammonia developer
which had been brought over from the collodion process.

The work was done with a solution of pyrogallol and dilute am-
monia, with the addition of ammonium bromide or potassium bromide,
and the results were delicate, but these negatives had a yellowish or
brownish stain, which coloring often unfavorably influenced the whole

GELATINE SILVER BROMIDE

433

gelatine layer of the image; these developers were also difficult to keep.

H. B. Berkeley, 14 in 1882, radically improved the pyrogallol de-
veloper by the addition of sodium sulphite, which protected the aque-
ous solutions of pyrogallol from rapidly turning brown and kept the
negatives developed with pyro from yellow stain. This was an
enormous advance, which affected not only the pyro developer but
also, what is more important, all modern organic developing substances
(hydroquinone, pyrocatechin metol, etc.).

Herbert Bowyer Berkeley (1851-1891) was the son of the Reverend
Conyers Berkeley, attended Uppingham College and devoted himself
in particular to chemistry, which he combined with his private studies
in photography; he wrote many papers for the technical journals.
Berkeley later entered the employment of the Platinotype Co. (1879)
and remained there until six months before his death. He contributed
greatly to the improvement of platinotype and had a large share in
bringing about its popularity among photographers. He is best known
for having introduced sodium sulphite in the pyrogallol developer
(1882), which preserved it from oxidation and improved the quality
of the negative. It was not long before Berkeley’s discovery was applied
to all other developers. Berkeley was an excellent photographer whose
work was admired in many exhibitions. He had the courage of his
convictions and was a good debater at society meetings, but was often
too aggressive to make friends. His health declined in the last years of
his life, and he went to Algiers, where he died in 1891 {Phot. Jour.,
February 20, 1891). 15

Mawson and Swan introduced potassium metabisulphite for pre-
serving pyrogallol solutions, in 1886, and for hydroquinone developers.

IRON OXALATE DEVELOPERS

Carey Lea 18 experimented in 1 877 with various developing substances
for iodine bromo-silver chloride negative papers and found potassium
ferrous oxalate especially effective. He dissolved precipitated ferrous
oxalate in a boiling potassium oxalate solution and stated that solutions
of ferrous sulphate with potassium oxalate were less to be recom-
mended. Later, in 1880, he suggested various complicated iron de-
velopers, which contained, besides oxalate, also phosphates, sulphates,
borates, etc. It escaped him that the best results could be obtained with
the simple potassium iron oxalate developer. 17

The author demonstrated this 18 and introduced the iron oxalate

GELATINE SILVER BROMIDE

434

developer by mixing two cold solutions of ferrous sulphate and potas-
sium oxalate. This developer produced brilliant grayish-black nega-
tives which offered great advantage over the yellowish-brown and
often foggy pyro-ammonia negatives of that time. The introduction
of the author’s iron oxalate developer greatly aided the general use of
gelatine dry plates, which is particularly emphasized by H. W. Vogel
in his report to the Vienna Photographiscbe Notizen ( 1 880, p. 1 ) .

ORGANIC DEVELOPER SUBSTANCES

W. de W. Abney published the alkaline hydroquinone developer
for gelatine silver bromide negative making in 1880. In the same year
the author and V. Toth, of Vienna, discovered that pyrocatechin
was suitable as an alkaline developer for dry plates. On this occasion
they gave precise data on the influence of isomerism in the bihydroxyl
derivatives of benzol. They observed that the para position in the bi-
valent phenols, which is present in the hydroquinone, shows a very
strong action in the alkaline developer on silver bromide; furthermore,
that the position given in the pyrocatechin causes a great developing
power, while resorcin (meta position) has no energy as a developer.

This rule for the developing strength of phenol derivatives was later
found correct also for other derivatives, for instance, paramidophe-
nol.

The history of substances for the organic photographic developers
is briefly as follows: in 1880 hydroquinone (Abney) and pyrocatechin
(Eder and Toth) became known as developers; then followed, in 1884,
hydroxylamine (Carl Egli and Arnold Spiller); in 1885 phenylhydra-
zine (Jacobsen). In 1888 Andresen was granted a patent for use of
p-phenylendiamine as developer; in 1889 Andresen recognized the
adaptability of certain naphthalene derivatives (eikonogen), and in
1891 he announced paramidophenol (rodinal) which is still generally
used.

To the chemist Dr. M. Andresen, who directed the company for
manufacture of aniline in Berlin, we are indebted for numerous pro-
gressive steps in the chemistry of developer substances, also for the
advance in other photochemical fields and for improvements in the
manufacture of dry plates.

Dr. Momme Andresen was born October 17, 1857, the son of An-
dreas Christian Andresen, the owner of an estate on the west Schles-
wig coast, went to elementary school at Risum, his birthplace, later to

GELATINE SILVER BROMIDE

435

the Wilhelm School at Niebiill. He studied natural sciences from 1875
to 1880, principally at the technical college in Dresden and at the
universities of Jena and Geneva. Between 1887 and 1911 he was em-
ployed as chemist by the company for aniline manufacture in Berlin
(Agfa) and as technical and scientific director of the photographic
department. Since 1 9 1 1 his connection with the firm has been that of
scientific collaborator.

Andresen took part in the successful investigation of the constitution
of quinone chloramides ( Journal f. prakt. Chemie, XXIII, 167, 435;
XXIV, 426; XXVIII, 422), as well as the constitution of saf ranine
( Berlin Ber. 1886, p. 2212). He discovered the a-napththol-e-disulpho
acid (German patent, No. 45776), which is also called Andresen acid.

Andresen recognized the great importance which belongs to the
ammonia residue NH 2 as an “effective group” among organic de-
veloper substances, and he discovered paraphenylendiamine (German
patent No. 46495, of January 8, 1888), Eikonogen (No. 50265, Octo-
ber 2, 1889), paramidophenol (rodinal) (No. 60174, January 27,
1891). He investigated the action of light on the diazo combinations
of naphthylamine, from which sprang a new diazotype process (Phot.
Korr., 1895; Jahrbuch, 1896, p. 260).

In 1898 he demonstrated that “permanent direct printing papers”
could be produced which possess, owing to an addition of dyes, the
maximum sensitivity in any chosen region of the spectrum from the
red end into the blue. He supplemented this with an investigation “Zur
Aktinometrie des Sonnenlichtes” (Phot. Korr., September, 1898).

Andresen is the author of Das latente Lichtbild, seine Entstehung und
Entavicklung (1913). and the Agfa-Photo-Handbuch (1922). He
wrote the section “Entwickler-Substanzen,” for the 5th and 6th edi-
tions of the Handbuch (1930, Vol. Ill, Part 2).

Very important was the discovery of metol, amidol, and glycin as
developers by the chemist Dr. A. Bogisch in the photographic depart-
ment of the chemical factory of J. Hauff, Feuerbach, near Stuttgart.
The metol developer is especially important for the rapid development
of instantaneous exposures and is very widely used in a mixture with
hydroquinone (metol-hydroquinone). It was introduced into practice
about 1893 for both negatives and positives. 10

In 1 899 Dr. Luppo-Cramer, who was at that time connected with
the chemical factory of Schering, in Berlin, made the observation that
a substitution bromo- or chloro-hydroquinone increased the strength

GELATINE SILVER BROMIDE

436

of the developer over the hydroquinone in alkaline developer, and he
called his product “Adurol.”

Great merit was achieved by Lumiere brothers and Seyewetz in the
photochemical laboratory of their dry-plate factory at Lyon. They
introduced “metochinon” (a complex compound of metol and hydro-
quinone), diamidoresorcin, hydramin (combination of hydroquinone
with para-phenylendiamine) , and have published many research papers
on the theory of developer substances ( Handbuch , 1930, Vol. III).

UTILIZATION OF TANNING PHOTOGRAPHIC GELATINE SILVER BROMIDE
FILMS BY PYROGALLOL DEVELOPERS FOR REPRODUCTION PHOTOGRAPHY

Gelatine silver bromide films present the image as a swelled relief
after development with alkaline pyrogallol without sulphite. The
author pointed out in 1881, in the English edition of his Modern Dry
Plates (p. 124), that this relief could be made sufficiently high so that
a mold could be made from the swelled gelatine image and used as
photomechanical printing plates (see also Handbuch, 1922, IV (3),
304).

Leon Warnerke, a Russian living in England, made in that same year
a much more important report on the property of the gelatine film
tanned with pyro developer, namely, that only those parts which had
not been exposed to light were soluble in warm water, while the ex-
posed parts, tanned by exposure, remained insoluble {Phot. News,
1881; Phot. Mitt., XVIII, 65,98, 235).

These relief images can be produced with fixed, as well as with un-
fixed, silver bromide paper prints, and they can be transferred in the
manner of pigment prints to other surfaces, as described in the sections
“Pigmentverfahren,” in Handbuch (1926, IV(2), 293, 395), and
“Heliogravure,” in Handbuch (1922, IV(3), 306).

This process was thoroughly elaborated by the ingenious amateur
photographer Warnerke and demonstrated by practical proofs. The
Royal Photographic Society of London awarded him a prize for the
process, but it met with no success commercially. He extended his
experiments by introducing the “silver pigment process” for intaglio
etching of copper plates, but was no more successful in this than in
the earlier process. Warnerke’s work became more important, how-
ever, when the original developing method found practical application
through the introduction of pyrocatechin in different forms by Gus-
tav Koppmann (1907 ) ; all this is exhaustively treated in the Handbuch
(1926, IV (2), 294).

GELATINE SILVER BROMIDE

437

FIXATION OF GELATINE DRY PLATES

Gelatine dry plates were always fixed with “hypo” (sodium thio-
sulphate). The organic developers, pyrogallol, hydroquinone, and
eikonogen sometimes indicated a so-called fogging tendency, which
had to be eliminated by immersion in acid-fixing solutions, alum baths,
and so forth , 16 in order to obtain clear negatives. The acidulation of
fixing baths with acids prevented the rapid decomposition of the fixing
salts.

In 1889 Professor Alex. Lainer, of Vienna, during his work at the
Graphische Lehr- und Versuchsanstalt, found that sulphites could
be mixed to a clear solution with fixing baths and that in this manner
fixation and removal of the fog were obtained in one manipulation. He
published this in the April number of the Phot. Korr. (1889, p. 171).
This was quite important in the use of the new developing agents that
made their appearance at that time.

Alexander Lainer (1858-1923) studied chemistry at the technical
college in Vienna, in 1882 taught physics, chemistry, and optics in the
photographic department of the government trade school at Salzburg,
and was called to the newly founded Graphische Lehr- und Versuchs-
anstalt, in Vienna, as professor of chemistry and physics (1888-1900).
He wrote, in 1889, a textbook of photochemistry, Lehrbuch der pho-
tographischen Chemie (1890; 2d ed., 1899); he published V ortrdge
iiber photographische Optik (1890); and Photoxylographie (1894);
and wrote on the utilization of the residue of precious metals and nu-
merous articles for photographic periodicals. During the course of his
studies on photographic developers he discovered that under certain
conditions the action of the developer is accelerated by the addition of
potassium iodide 20 (in contrast to potassium bromide), which in the
technical literature was designated as the “Lainer effect” and was the
starting point of many investigations ( Handbuch , 1927, II (1), 223,
by Liippo-Cramer). He resigned from the institution in 1900 in order
to establish his factory for photographic papers and plates, which later
became so well known. After his death, in 1923, his son Oscar took
over the business and merged it with that of Hrdlicka.

It was just at this time that M. Andresen, in Berlin, invented the
eikonogen developer which the Agfa Co. brought into the market.
This developer tended greatly to the formation of fog, but this was
eliminated by Lainer’s acid fixing bath, by which clear, gray-black
negatives were obtained. A few months after Lainer’s article in the

438 GELATINE SILVER BROMIDE

Phot. Korr. on his acid fixing bath, Andresen prescribed, in the di-
rections for the use of eikonogen, under the title “Fixierbad fur Plat-
ten, welche mit Eikonogen entwickelt sind,” the use of the acid fixing
bath. It consisted of 2 50 g. of hypo, 50 g. sodium bisulphite dissolved
in 1,000 parts water. These salts were later put on the market, in an-
hydrous state in the shape of cartridges.

The generally used “acid sulphite solution” of today for the acidu-
lation of fixing baths, consisting of sodium bisulphite with excess of
sulphurous acid, was introduced by the author in August, 1889 {Phot.
Korr., 1889, p. 200; Handbuch, 1930, III (2), 200).

REDUCTION OF GELATINE SILVER BROMIDE IMAGES

The reduction of both negatives and positives was carried on during
the years of the Talbotype and of the collodion process according to
various methods, which are described in special chapters of the
Handbuch (Vols. II and III).

After the publication by the author of the mechanism of the reaction
of potassium ferricyanide on silver, in 1876, it was known that ferro-
cyanide of silver is formed by this procedure. This is soluble in hypo.
The reduction by the treatment of silver images with potassium ferri-
cyanide and subsequent fixation is based on this reaction.

The English worker E. Howard Farmer was the inventor of this
mixed reduction bath, consisting of hypo with the addition of potassium
ferricyanide (1883). The reduction occurs in one bath and is there-
fore more easily controlled. This Farmer’s reducer became very im-
portant in photochemistry. 21 Reduction with potassium permanganate
was invented by Namias (see Chapter XCVI). The reduction with
ammonium persulphate (1898) and also cerisulphate (1900) were
found by Lumiere and Seyewetz {Handbuch, 1903, III, 556, 558).

Intensification of gelatine silver bromide images followed methods
analogous to those employed with collodion negatives.

Chapter LX., gradual increase in sensi-
tivity OF PHOTOGRAPHIC PROCESSES FROM 1827
UNTIL THE PRESENT TIME

A review of the gradual increase in sensitivity of the photographic
processes from the invention of photography until the present time is
very interesting . 1

Engraving with asphalt

Daguerreotypy with silver iodide

Talbotype with gallic acid developer

Wet collodion process

Collodion silver bromide emulsion

Gelatine silver bromide at the time of invention

Gelatine silver bromide

Year

Exposure

1827

6 hours

1839

30 minutes

1841

1851

10 seconds

1864

15 “

1878

1-1/200 second

1900

1/1000 “

The spectral sensitivity of the daguerreotype plate was very limited,
extending from the beginning of the ultraviolet to the blue, and em-
braced only a small part of the visible spectrum. The use of quartz (rock
crystal) lenses broadened the field into the invisible ultraviolet 2 and
the use of optical sensitizers far into the dark red. 3 Later investigations
produced sensitizers which reached into wavelengths of 900 or 1 ,000
into the infrared. 4 A diagram in the 1932 German ed. of this History
(p. 6 1 1 ) shows this development clearly. 5

Chapter LXI. gelatine silver bromide

PAPER FOR PRINTS AND ENLARGEMENTS

The modern photographic printing method on gelatine silver bromide
paper was begun in England, even as the entire technique of gelatine
emulsions was evolved there. As early as 1 874 Peter Mawdsley, the
founder of the Liverpool Dry-Plate Co., pointed out, in the Yearbook
of Photography (1874, p. 116), the possibility of utilizing gelatine
silver bromide papers for photographic printing. He advertised this
manufactured article and called attention to its adaptability for the
enlargement of negatives by the projection apparatus, emphasizing
the fact that such silver bromide prints were very suitable to being
painted over. Nevertheless he died unsuccessful and very poor.

GELATINE SILVER BROMIDE PAPER

44 °

Sir Joseph Wilson Swan, co-inventor with Edison of the carbon
filament bulb for electric illumination and inventor of the pigment
process, was more successful in the following year. He was a manu-
facturer of importance, who in 1879 undertook the manufacture of
“bromide printing paper” on a large scale, and applied for an English
patent (No. 2986, 1879) on his product. This patent was granted
because of the peculiar patent laws in England, which require no proof
of originality. While it is unjust to call him the inventor of this positive
printing paper, it was he who introduced it into practice. He foresaw
clearly that this process, for which a short exposure in weak artificial
light sufficed, would attain universal use. 1 All this, however, must not
interfere with Peter Mawdsley’s priority rights to the invention.

About the same time as Swan, E. Lamy entered the field in France
and manufactured silver bromide paper successfully, erecting an effi-
cient factory at Courbevoie (Seine) . Later, factories were started in
England by Morgan and Kidd, at Richmond, by Marion, and others.

The first textbook concerning the photographic silver bromide
printing paper process came from the pen of John Burgess, under the
title The Argentic Gelatino-Bromide Worker's Guide, with Instruc-
tion for U se for Rapid Positive Printing ( 1 880) . It was illustrated with
a silver bromide print by Morgan & Co., of Greenwich. After seven
years experience in the production of gelatine dry plates, Burgess,
jointly with W. T. Morgan and assisted by his manager, R. L. Kidd,
successfully introduced the manufacture and sale of silver bromide
papers.

Silver bromide paper, as a medium for rapid printing with artificial
light and for enlargements, was generally adopted about 1880. When,
in 1884, the American firm of Eastman and Co. at Rochester con-
structed the first efficient emulsion coating machine to coat negative
paper and films, the joint work of Walker and Eastman, a large in-
dustry in this field came into existence, which naturally first revolu-
tionized the photographic printing process in the United States and
later brought this technical process to a complete success.

The scientist Dr. F. Stolze, of Berlin (the inventor of the gelatine
neutral tint wedge and editor of the Photographisches W ochenblatt) ,
was the first manufacturer of silver bromide paper in Germany. He
started the production of silver bromide paper in Berlin on a small scale,
but could produce only a relatively small amount; in 1 894 he still could
not make more than one hundred meters (about 328 feet) a week.

GELATINE SILVER BROMIDE PAPER

44 1

For mass production the invention of the printing automat (rapid
printing machine) was important. The first to construct a printing
automat which satisfied the practical demands was the engineer Schlot-
terhoss, 2 in Vienna (1852-1892). In 1883 he patented an exposure
automat in which the sensitized paper was advanced and exposed by
clockwork and which could be used in artificial light or daylight.

By the use of the less sensitive silver chloride paper Schlotterhoss
could produce in diffused daylight and in electric light four hundred
to five hundred prints in an hour; in gaslight, sixty prints; and thirty
cyanotype and platinum prints an hour in direct sunlight. They were
then developed and fixed. Schlotterhoss erected his machine in Dr. E.
Just’s 3 photographic paper factory, Vienna, and produced experi-
mentally large editions of serial pictures on both gelatine silver bro-
mide and silver chloride paper. The invention, however, met with no
appreciation at that time, since there existed no market for large edi-
tions of such pictures, no matter how beautiful they were. Just as
unsuccessful was the application for the first time, by Schlotterhoss,
in 1883, of the rapid photographic printing process to criminal pho-
tography, although police headquarters at Vienna had succeeded that
year in identifying and arresting the dangerous anarchist Stellmacher
through the work of Schlotterhoss, who printed photographically in
one night the illustrated notices for the criminal’s apprehension. While
greatly pleased, the Vienna police authorities of that time failed to
introduce the process, and it did not take its proper place in criminal
procedure until 1 890, when Alphonse Bertillon brought it to the front.
Art dealers were indifferent at that time to this novel and rapid method,
and, sadly enough, the engineer Schlotterhoss, who had sacrificed his
whole fortune to this invention, died in poverty.

Photographic printing machines on a large scale were successfully
introduced by Arthur Schwarz, who founded (1893-1894) in Berlin
the Neue Photographische Gesellschaft (N. P. G.), for the production
of the so-called “kilometer photography” for illustrating purposes,
with which he combined his large art and picture postcard business.

Arthur Schwarz (b. 1862) was active in the photographic business
from 1887 in London and New York, where various machines for
printing silver bromide paper in large rolls were then in operation.
In 1892 A. Schwarz, with Benjamin Falk, took over Urie’s patent for
an automatic printing machine for silver bromide paper in rolls. They
started an establishment for this purpose in New York City and per-

GELATINE SILVER BROMIDE PAPER

442

fected this process by adding a developing and finishing machine.
With the first specimen prints from this machine on paper rolls,
Schwarz came to Germany and founded, in Berlin, July 4, 1 894, the
Neue Photographische Gesellschaft. When he found himself unable
to buy the necessary silver bromide paper in sufficient quantity for
his printing and developing automats, he erected a factory and made
the paper himself. In January, 1895, the manufacture was started with
the first machines, which were built in the United States. 4 To Arthur
Schwarz must be credited the first practical introduction of the modem
mechanical silver bromide printing process in Germany.

The silver bromide papers produced by the Neue Photographische
Gesellschaft were offered for sale in 1894 in a variety of weights and
surface textures (mat and glossy) . The Neue Photographische Gesell-
schaft was incorporated in 1 899, having established in 1 898 a branch,
the Societe Photographique, in Rueil, France, and the Rotary Photo-
graphic Co. in London.

Glossy papers were produced on a base of permanent white (Ba S 0 4 )
and on somewhat hardened gelatine. In the first eighteen years in the
Berlin factory, Arthur Schwarz emulsified forty million meters (about
1 3 1 million feet) of paper and produced twenty-eight million meters
(65 '/ 2 million feet) of pictures. These large figures caused him to use
the name “kilometer photography,” or, as we would say, “photography
by the mile.” After the World War the Berlin Neue Photographische
Gesellschaft merged with the Dresden Ika Co.

The Eastman Kodak Co. was followed in 1900 by a long list of well-
known firms, of which many still exist today in England as well as in
Germany and France; a new industry for the production of printing
and developing papers was started, and also an industry which dealt
with their use by automatic machines (Wentzel, Handbuch, 1930,
Vol. III).

MAT SILVER BROMIDE PAPERS

Mat surfaced silver bromide papers were produced by Pauli and
Ferran by the use of starch in place of gelatine {Phot. News, 1879,
p. 439). G. J. Junk used a starch paste for making mat silver bromide
prints on paper and linen (D. R. P. October 19, 1893), while the East-
man Kodak Co. produced, in 1 894, a mat silver bromide paper called
“platino,” by emulsifying silver bromide in gelatine and adding starch
flour in a nonpasty condition.

POSITIVE PAPER PRINTS

443

These mat silver bromide papers displaced to a large extent the
glossy papers then generally used, such as the earlier printing-out papers
(albumen paper, mat albumen, pigment prints, platinum printing) in
the everyday business of commercial and artistic photography; they
were also extensively used in the illustration of periodicals, scientific
works (Roentgen photography, microphotography, astrophotogra-
phy), but in many of these uses glossy papers reappeared, owing to
their sharp delineation of detail.

Chapter LXII. the discovery of gelatino-

SILVER CHLORIDE FOR TRANSPARENCIES AND
POSITIVE PAPER IMAGES BY CHEMICAL DEVELOP-
MENT ( 1 8 8 1 ) ; ARTIFICIAL LIGHT PAPERS

The production of diapositives and positive paper prints with gela-
tine silver chloride emulsion and chemical development was invented
and published by the author and G. Pizzighelli, in Vienna (1881). 1
Until that time only the production of gelatine silver chloride papers
with excess silver nitrate and the development with gallic acid, etc.,
after the manner of the Talbotype process, was known in photographic
practice.

In the seventies of the last century attention was centered only in
gelatine silver bromide emulsions, and it was natural that ideas turned
to the making of silver chloride emulsions. W. de W. Abney attempted
to develop gelatine silver chloride emulsion plates with ferrous oxalate
(Brit. Jour. Phot., 1879, p. 614). He found that these were much less
sensitive to light than were silver bromide plates, but were easier to
reduce, which caused a strong formation of fog. Abney deserves credit
for having demonstrated that gelatine silver chloride emulsions were
unsuitable for negative making; the fogged, grayish-black images were
useless. No one knew at that time, not even Abney, that with chemical
development gelatine silver chloride emulsions could produce beauti-
ful diapositives in warm colors as well as photographic prints. The
failure of his experiments had a discouraging effect on other research
workers.

Two years later the author was busy with gelatine silver halide emul-
sions. In 1881 he was assistant to Professor J. J. Pohl, in chemical

POSITIVE PAPER PRINTS

444

technology, at the technical college at Vienna. There was only a small
darkroom and no studio at the college, and his photographic experi-
ments were made with prints from negatives. This experiment led the
author to discover the very favorable behavior of silver chloride with
the weak reducing ammonium-ferro-citrate developer and the weak
alkaline hydroquinone developer; in these experiments he used gela-
tine silver chloride emulsions made with an excess of sodium chloride.
For subsequent work he joined with his friend Captain Giuseppe
Pizzighelli; the latter was director of the photographic branch of the
army commission on technical administration, at Vienna, and had at
his disposal spacious working facilities, as well as studios and technical
assistants. It was there that the photographic work with the gelatine
silver chloride emulsions was further elaborated.

The author and Pizzighelli recognized the superiority of gelatine
silver chloride emulsions chemically developed over the earlier silver
chloride emulsions which had been prepared with other binding agents,
and they perfected methods by which, depending on the mode of
development, prints of variable colors (red, yellow, violet, and brown)
could be obtained, in contrast to the grayish-black color of silver bro-
mide prints. They also realized the extreme fineness of the gelatine
silver chloride grain.

They reported their work briefly to the Vienna Academy of
Sciences, January 13,1881 (LXXXIII, 144) , and in Phot. Korr. (1881).
There was also published a pamphlet by Eder and Pizzighelli: Die
Pbotograpbie mit Chlorsilber gelatine und cbemiscber Entavicklung
nebst einer praktischen Anleitung zur rase ben Herstellung von Dia-
positiven, Stereos kopbildern, Fensterbildern, Duplikat-N egativen,
Vergrosserungen; Kopien auf Papier . . . (Vienna and Leipzig, 1881).

In this pamphlet they described for the first time the method of pro-
duction of gelatine silver chloride emulsions with excess of chloride
and suggested the development, heretofore unknown, of clear silver
chloride images with ammonium-ferrocitrate and organic developers
(alkaline hydroquinone and others) . They also showed that the latent
silver chloride image can be transformed to a latent silver-bromide
image, capable of development, in the usual way by treatment with
soluble bromides. The results of the experiments with pure gelatine
silver chloride emulsions were satisfactory. In order to obtain speci-
mens for exhibition, the author and Pizzighelli made diapositives from
original portrait negatives (collodion) taken by the court photog-

POSITIVE PAPER PRINTS

445

rapher, Victor Angerer, of Vienna, and exhibited the finished results
in a series of diapositives at the International Exposition, on the occa-
sion of the twentieth anniversary of the Photographic Society of Vi-
enna, in 1 88 1. There for the first time were shown silver chloride de-
veloped photographs in tones of various warm colors unknown up to
that time. The warmest bright red shades were developed with hydro-
quinone and ammonium carbonate, the brownish tones with am-
monium-ferro-citrate, the greenish brown tones with alkaline gallic
acid solution, and so forth. The beautiful effect of the toning of such
developed pictures by thiocyanogen gold baths could be seen before
fixation, which produced the warm, violet-black transparent color, 2
while silver bromide prints do not change their cold black tone in gold
baths. This diapositive exhibit was awarded the gold-enamel medal by
the Vienna Photographic Society.

In the same year the author sent some of these gelatine silver chloride
diapositives, chemically developed, to Captain Abney at London, who
presented them to the South Kensington Museum. The English techni-
cal societies also took an interest in this, and the Royal Photographic
Society of Great Britain, in 1884, awarded to the author its “Progress
Medal.”

Others who occupied themselves with the new diapositive process
were Cowan, in London, and Scolik and Schattera, in Vienna (1891),
Unger and Hoffmann, in Dresden (1892), Perutz in Munich, Edwards,
at the Britannia Works in Ilford, England (1893), Mawson, Swan,
Cadett, and Neal, in England, and others.

Of greater importance, however, was the production of positive
paper prints by means of the gelatine silver chloride developing process,
which was first described in 1881 in the above-mentioned pamphlet
by the author and Pizzighelli.

The manufacture of gelatine silver chloride development paper on
a large scale, based on the publications of the author and Pizzighelli,
was first taken up in Vienna, by Dr. E. Just, at the end of 1882. Dr.
Just was the first to employ one of Schlotterhoss’s printing automats,
then newly invented. He printed long strips of negatives on gelatine
silver chloride paper, which he preferred to silver bromide paper. A
large number of such pictures were made for publication and presented
to the Vienna Photographic Society; a series of these prints belonging
to the author have been preserved in the Technical Museum at Vienna.
Most of them were developed with ferro-acetate. Dr. Just recognized

446 POSITIVE PAPER PRINTS

also the influence of the time of exposure and development on the
tone or color of the developed silver chloride prints, which he graph-
ically demonstrated by systematic grouping. Such a group is preserved
in the Graphische Lehr- und Versuchsanstalt, in Vienna, a gift of Dr.
Just to the author.

Dr. E. Just, born 1 846, in Saxony, was a chemist who came to Vienna
and founded a factory for the manufacture of photographic papers
(albumen paper, silver printing paper, etc.). He learned of gelatine
silver chloride emulsions on glass and paper at the lectures by the
author and Pizzighelli before the Photographic Society, and began
their manufacture according to the directions of the inventors, who
received no financial recognition. Dr. Just also wrote two pamphlets:
Der Positive-Prozess auf Gelatine-Emulsions-Papier (Vienna, 1885)
and Leitfaden fur den Positiv-Entwicklungs-Prozess auf Gelatine
Emulsionspapier (Vienna, 1890).

Somewhat later than Dr. Just, L. Warnerke, in London, in 1889,
took up the production of gelatine silver chloride paper. Wamerke
realized the importance of this novel printing method, owing to the
beauty of the results which could be obtained (warm tones in contrast
with the cold tones of bromide pictures), and he called this process
“the printing process of the future.”

Notwithstanding all these successes, the great period of the general
use of gelatine silver chloride papers had not yet arrived. The introduc-
tion of velox paper, accompanied by a tremendous advertising cam-
paign, commenced the victorious course of the gelatine silver chloride
printing process. Carrol Bernard Neblette, in his Photography (Lon-
don, 1 92 7, p. 3 2 ) , describes the invention, but his statement is incorrect.
He writes:

In 1893 Velox, the first of the “gaslight” papers, was introduced by the
Nepera Chemical Company from the formula of Dr. Leo Baekeland.
This is a chloride emulsion developing-out paper without free silver,
which is very much slower than bromide paper and can be handled in a
brighter light. Since the advent of Velox many other similar brands have
appeared both in this country and England, and indeed all over the world,
and are now by far the most widely used papers for positive printing.

This, however, is word for word a characteristic description of the
process invented by the author and Pizzighelli in 1 88 1 , of gelatine
silver chloride emulsion (produced with excess of sodium chloride)
and chemically developed. Baekeland had copied the earlier process,

POSITIVE PAPER PRINTS

447

perhaps unconsciously, with his silver chloride paper and had given
it a new name. It must be added that the Eastman Kodak Co. later
took over the manufacture of velox paper, retaining the name of this
gelatine silver chloride paper, and that these papers were also made
by other manufacturers in enormous quantities and sold at great profits.
This velox paper can be demonstrated to be nothing else than gelatine
silver chloride paper, chemically developed. It is because of these
earlier Eder-Pizzighelli gelatine silver chloride emulsions that the later
inventors were not successful in patenting their productions and why
the Ansco Co., and others also, were able to produce these papers.
But the real inventors of this product, which became so profitable an
investment, were never mentioned in America (Phot. Jour., 1930; also
Phot. Indust., 1930).

Mr. Neblette loyally corrected his error in the second edition of his
work (1931, p. 32).

Later, Liesegang, in Diisseldorf, put on the market “pan” paper,
that is, gelatine silver chloride paper. In 1903 the use of the mechanical
silver chloride printing process was revived by Linnekampf’s Aristo-
phot Co. for printing art subjects with warm red tones. At Vienna
a rapid-printing concern, Kilophot, was started later by Aug. Leutner
(1858-1927), which produced gelatine silver chloride papers in dif-
ferent grades: “normal” papers with silver chloride gelatine, “contrast”
papers with iodide added according to the Eder-Pizzighelli directions,
and “soft” papers with bromide added. Many other manufacturers
followed this differentiation of papers by their scale of contrasts.

GELATINE SILVER BROMO-CHLORIDE EMULSIONS FOR PAPER
PRINTS AND POSITIVE MOVING PICTURE FILMS

Gelatine silver bromo-chloride emulsions, which are more sensitive
than pure silver chloride emulsions, but produce warmer (brown) tones
than pure silver bromide emulsions, were first described by the author
in 1883. He published the advantages of these bromo-chloride emul-
sions for paper prints and diapositives in the Photographic News
(January, 1883, p. 98) in one original report. The author selected the
English periodical edited by Baden-Pritchard, for whom he acted as
Vienna correspondent, because as a weekly publication it offered an
earlier means of publication than did the German technical journals,
which reprinted this report on silver bromo-chloride emulsions some-
what later. By this invention the author created the large class of chloro-

448 POSITIVE PAPER PRINTS

brom silver “portrait” development papers and the chloro-brom-cine
positive films, which are produced in millions of feet. Chloro-brom
plates for lantern slides and transparencies were first made on a large
scale in England ( Handbuch , 1903, Vol.III); while the author’s chloro-
brom paper was not manufactured wholesale and introduced into
photographic practice until several years after its publication by the
English manufacturer as “alpha” paper. Later it was manufactured
in Germany as “tula” paper (Liesegang) and as “lenta” paper (Neue
Phot. Co., in Berlin) ; still later as “clorona” paper (Ilford Co., London) ;
and by many others ( Handbuch , 1930, Vol. Ill, Part 1).

ERRONEOUS CONFUSION OF SILVER CHLORIDE EMULSIONS WITH CHEMICAL

DEVELOPERS WITH THE PRINTING-OUT PROCESS USING SILVER CHLO-
RIDE EMULSIONS WITH EXCESS OF SILVER NITRATE

The author wrote on this subject in Phot. Industrie (1930, XXVIII,
855) as follows:

Until the beginning of the present century the fact was recognized, in
the history of photography, that the production of diapositives and posi-
tive paper prints with gelatine silver chloride emulsions and chemical de-
velopment was first published in 1881 by the author and G. Pizzighelli in
Vienna.

Later arose erroneous confusion of this process with the entirely differ-
ent printing-out method with gelatine silver chloride emulsions with ex-
cess silver nitrate (aristo paper). This error led some historical writers
into confusion, which necessitates that we enter into the facts here more
closely. In C. B. Neblette’s Photography (London, 1927, p. 31) it is
stated: As early as 1 8 66 Palmer and Smith showed a paper coated with an
emulsion of gelatinochloride of silver for use in positive printing (Phot.
News, 1865, pp. 613, 614 and 1866, pp. 24 35, 36). Further details were
given by this author and Captain Pizzighelli, Captain Abney, and W. T.
Wilkinson in 1881.

This statement of Mr. Neblette’s is erroneous; Palmer and Smith did
not invent gelatine silver chloride emulsions with chemical development.
Neither in the original publication by Palmer nor in that by W. H. Smith
in 1866 is there to be found one word about gelatine silver chloride emul-
sions with chemical development.

This can be proved. Palmer wrote on “enlargements on canvas” (on
the pages cited above in Phot. News) that he had suspended silver chlo-
ride in gelatine, but had coated the canvas “with such minute quantities”
that neither heat nor moisture impaired or cracked it. He stated, “It is
developed without gallic acid, neither gelatine nor any hygroscopic sub-

SENSITOMETRY

449

stance.” This definition contained no word pointing to chemical develop-
ment.

Now let us also examine closely the article by W. H. Smith in the Pho-
tographic News (1866, p. 36). There is no mention whatever by Smith
of any development. Probably he refers to a direct printing-out paper,
undeveloped, as the description of the print, “the colour is rich, delicate
and transparent,” seems to indicate. This entirely contradicts Neblette’s
statement quoted above.

Since English and American periodicals continued to describe incor-
rectly the history of the invention of silver chloride emulsions and of
silver bromo-chloride emulsions, the author demanded the rights of
priority for himself and Pizzighelli in the Photographic Journal of the
Royal Photographic Society of Great Britain in August, 1930 (also
Photographische Industrie, 1930, XXVIII, 855-56). This request re-
sulted in Neblette’s dropping the above-mentioned erroneous state-
ment in the second edition of his Photography .

Chapter LXIII. calculation of exposure,

DETERMINATION OF PHOTOGRAPHIC SPEEDS, SEN-
SITOMETRY, AND THE LAWS GOVERNING DENSITY

The registering photometer of Landriani is reported in Chapter
XVII. Exposure meters which are based on the appearance of a standard
tint of gray color on silver chloride paper were invented by Jordan and
Malagutti (1839), Heeren (1844), Hunt (1845), Claudet (1848), and
Schall (1853). Bunsen and Roscoe, however, in 1861, first brought
order into this field by the introduction of their standard gray with
one thousand parts of zinc oxide and one part soot (“Sensitometry,”
in Handbuch, 1930, Vol. Ill, Part 4).

Exposure meters with silver salt papers and normal gray tints with
tables were introduced by Stanley (1886), Wynne (1893), Alfred
Watkins (“Standard Exposure Meter”) 1890, (W. G.) Watkins
(“Beemeter”), and others.

Of purely optical exposure meters we mention only Decoudin,
“Photometre photographique” (with graduated paper scale, 1888),
and Heyde, “Aktinometer” (1905), ( Handbuch , 1912,1 (3), 122).

A comprehensive collection of actinometers, exposure meters, and

SENSITOMETRY

45 °

sensitometers was arranged for exhibition by Walter Clark in the
Museum of Science, South Kensington, London, in 1927, for the Royal
Photographic Society of Great Britain. The list of the exhibits is printed
in the supplement to the catalogue in the Photographic Journal. The
author began a similar complete collection for the Graphische Lehr-
und Versuchsanstalt, in Vienna, as a practical aid in his lectures.

The first exposure tables were published by C. F. Albanus ( 1 844) .
A very complete set of tables was given by Hurter and Driffield (“Ac-
tinograph,” 1888). All later tables of this kind are based on the meas-
urements of Bunsen and Roscoe (1858) which connect the activity of
sunlight with the position of the sun (time of the day and year) .

From the fifties of the last century, when the daguerreotype process
was being abandoned and the wet collodion process, collodion dry
plates, and silver bromide collodion made their appearance, the wet
collodion plate was the ideal of sensitivity in photographic plates, that
is, the sensitivity of such a plate was regarded as normal. This standard
of sensitometry, however, was very inexact, because it varied with the
preparation of the collodion.

We shall pass over the earliest experiments in this field, which are
exhaustively described in the Handbuch ( 1 9 3 o, Vol. Ill, Part 4) . Sensi-
tometry became of actual value only with the invention of gelatine
silver bromide plates with their different degrees of sensitivity.

The first practically serviceable device for measuring exposures was
the sensitometer invented in 1880 by Leon Warner ke, which was
placed on the market in its final form in England. 1 It was widely appre-
ciated, because with its aid one could classify the sensitivity of the
extremely variable sensitive silver bromide plates with sufficient ex-
actness. This sensitometer consisted of a gelatine intensity scale marked
with India ink in graduated spaces; the light source was a blue phos-
phorescent plate, which was illuminated, as required, by magnesium
light.

Warnerke rendered a great service to dry plate manufacturers and
photographers with his sensitometer, because previous to its intro-
duction they had been obliged to rely on the uncertain estimate of
sensitivity based on mere guesswork. Ten degrees of Warnerke’s
sensitometer were at that time considered to be equal to the average
sensitivity of a wet collodion plate. The ideal of the eighties for silver
bromide emulsions was the sensitivity of plates equal to the highest
number (twenty-five degrees) of the Warnerke’s sensitometer; this

SENSITOMETRY

45i

corresponded approximately to sixty times greater sensitivity than a wet
collodion plate. Ordinary portrait plates had, even around 1890, the
medium sensitivity of twenty degrees, Warnerke, equal to ten degrees
of the later sensitometer of Scheiner. Instantaneous plates had twenty-
four to twenty-five degrees Warnerke (about sixteen to eighteen de-
grees Scheiner), which at that time was still considered a high degree
of sensitivity. Today manufacturers supply plates of twenty-four to
twenty-five degrees Scheiner, which are several hundred times more
sensitive than wet collodion plates.

Wamerke’s biography: Leon Warnerke was bom in 1837 in Russia
(some less reliable sources say in Hungary) . 2 He was a civil engineer,
but devoted himself entirely to photography. He spent his youth in
St. Petersburg. He came to London in 1870, started a private photo-
chemical laboratory, invented the roll holder with silver bromide col-
lodion stripping paper. He worked a great deal with silver bromide
collodion, received a prize from Belgium in 1877, for his work in this
field, and in 1881 the Progress Medal of the Royal Photographic So-
ciety of Great Britain. He gave lectures before the photographic
societies of England, France, Belgium, and Germany, but never came
to Austria-Hungary.

At the end of the seventies he investigated gelatine silver bromide
emulsions and discovered the tanning action of pyrogallol in the de-
velopment of silver bromide plates. In 1 880 he founded, at St. Peters-
burg, a photographic firm and a technical journal. He was also finan-
cially interested in the manufacture of dry plates in Russia. Later he
produced in England gelatine silver chloride paper, which he had
greatly improved. His actinometer and his sensitometer are well known
( Handbuch , 1 9 1 2 , Vol. I, Part 3 ) . It was W arnerke who personally in-
troduced in England the Goerz double anastigmat constructed by the
Berlin optician Goerz; he also was the first to demonstrate there the
Lippmann color process, and in 1893 he also showed Lumiere’s auto-
chrome process.

About 1898 Warnerke received a rather large sum of money
(about 5,000 pounds) in Russian bank notes as payment on account
of a photographic invention. When these notes were exchanged in
France, some of them proved to be counterfeits. From a false sense of
discretion he refused to disclose the party from whom he had re-
ceived the notes and was convicted, not for counterfeiting, but for
passing the counterfeit notes; sentence, however, was suspended. He

SENSITOMETRY

452

retired after this to Geneva and lived in almost complete solitude,
dying there in straightened circumstances on October 7, 1900. After
his death his sensitometer was no longer manufactured, and today
specimens of it can be seen only in museums.

The English chemist Chapman Jones introduced, in 1901, a similar
instrument with progressively graduated squares of neutral gray den-
sities, numbered 1 to 25, in combination with gelatine color filters,
which enjoyed wide popularity under the name “Chapman Jones
plate tester.” It is still used, but it furnishes no exact measurements.
Jones also studied the chemical reaction equations in negative intensi-
fication with mercury bromide and sodium sulphite, as well as in in-
tensification with mercury chloride and potassium cyanide.

Warnerke’s sensitometer was displaced, in 1894, by sensitometers
with rotating wheels. The first of these were made at the time of Bunsen
and Roscoe (1862). Professor E. Mach constructed the first sensitom-
eter of this kind ( 1865). In 1 890 Hurter and Driffield used the rotating
sector-wheel sensitometer in their extensive sensitometric investiga-
tions ( Handbuch , 1930, Vol. Ill, Part 4).

The astronomer Dr. Julius Scheiner (1858-1913) constructed, in
1 894, a more exact sensitometer of this kind. He was at first assistant
at the observatory at Bonn, and in 1 894 observer at the astrophysical
observatory at Potsdam. In 1895 he was professor of astrophysics at the
university at Berlin. 3 He made his sensitometer public in June, 1 894,
with continuous curved apertures and shuttered benzine light. The
author gave the instrument the shape which was later generally adopted,
having a series of steps standardized with the Hefner amylacetate
standard lamp, and presented it before the International Chemical
Congress at Vienna in 1898. Scheiner’s sensitometer scale, reduced to
candle power per second per meter, is still used today in German and
Austrian industry and commerce. Following the suggestion by this
author, given at the International Chemical Congress of Vienna, the
Secco-Film Co. of Berlin (Dr. Hesekiel, Moh & Co.) was the first
(March 6, 1899) firm to indicate the sensitivity of its films by Scheiner
degrees printed on the package.

The principle of tube photometers was stated by Heinrich Wilhelm
Dove in 1861 (Poggend./lTMM/., 1861, CXIV, 145) and was later applied
by Bunsen and Roscoe, then came Taylor (1869), Mucklow and
Spurge (1881), H. W. Vogel and the author ( Handbuch , 1930, Vol.
Ill, Part 4), with various kinds of tube photometers.

SENSITOMETRY

453

The invention of the gelatine neutral gray wedge sensitometer in
1883, by the German scientist Dr. Franz Stolze (1830-1910), was im-
portant. Stolze lived in Berlin and published fundamental articles in
this field ( Pbotographische Wochenblatt, 1883, p. 17, edited by him)/

In 19 1 1 Professor Emanuel Goldberg, 6 of Leipzig, published in-
structions for the production of an improved form of such wedges,
which later found general use and is considered to be a very definite
advance. Dr. F. Stolze’s priority had been entirely forgotten, and the
author had to take up the fight for the recognition of priority he de-
served.

Notwithstanding the fact that the Stolze-Goldberg gray wedge
had long been known, no sensitometers equipped with it were manu-
factured for industry and commerce. This actuated the author to
bring out, in 1919, his “Eder-Hecht wedge sensitometer,” 6 which
Goldberg had not done up to that time. This is shown by a letter of
Dr. Eduard Schloemann, manager of the Kino Film Co., Diiren, Ger-
many, dated April 27, 1921, which reads:

With greatest interest I have followed your work on the Eder-Hecht
wedge sensitometer, and I promise myself great advantages from the use
of this instrument for the photographic industry. I welcome the appear-
ance of your sensitometer so much the more, since the Goldberg wedge
sensitometer never made its appearance in practical form. Notwithstand-
ing repeated announcements and since I have been repeatedly consoled
personally by Professor Goldberg with promises for a later date. ... I
have bought two of your sensitometers from the Herlango Co. and intend
to have them used continually in our work.

[^Signed:] Dr. phil. Ed. Schloemann.

The Eder-Hecht wedge sensitometer was provided with spectro-
scopically standardized color filters (red, yellow, green, blue) and a
scale referring to candle-meter seconds by using a free-burning stand-
ard light source of 2 mg. of magnesium ribbon, standardized as a white
light source (German Musterschutz, No. 155,306, January 8, 1921).
For literature on this subject see the author’s Ein neues Graukeil-Pho-
tometer fur Sensitometrie, pbotographische Ropier verfahren und
Lichtmessungen (1920); Phot. Korr. (September, 1919), and Hand-
buch (1930, Vol. Ill, Part 4).

The investigations of sensitivity by Hurter and Driffield were very
successful. Ferdinand Hurter (1844-1898) was born in Switzerland,
went to Manchester, England, in 1867, where he was employed by

454

SENSITOMETRY

the United Alkali Co. as chemist. Vero Charles Driffield (1848-1915)
interested himself in photography and made Hurter acquainted with
it in 1876. On May 7, 1890, they published jointly their fundamental
work, Photochemical Investigations and a New Method of Determina-
tion of the Sensitiveness of Photographic Plates, in which they plotted
curves having as coordinates, the logarithm of the light intensity and
the density of the plate.

These investigations are described in detail in the Handbuch (1930,
Vol. 111(4), “Sensitometry”). The collected writings of Hurter and
Driffield were published in Memorial Volume by the Royal Photo-
graphic Society of Great Britain in 1920. The further progress of
sensitivity is recorded in the proceedings of the International Congress
of Photography, London (1928), and Dresden (1931).

LAWS OF DENSITY FOR PHOTOGRAPHIC PLATES AND PAPERS

The reciprocity law of Bunsen and Roscoe is considered funda-
mental, and it is E = i ■ t. However, it works only within certain limits,
and the photographic process of intensification exhibits many devia-
tions, which on their part again are subject to definite rules.

The astronomer P. J. C. Janssen stated, in 1881, that during the proc-
ess of photographic development the action of light, E, does not grow
in proportion to the intensity. Later, W. de W. Abney made very
thorough studies of the exceptions to the law of reciprocity on silver
bromide gelatine plates (1892-1 894) 7 and measured the deviations.
He asserted that the law broke down completely when dealing with
very small light intensities.

Abney stated, in 1894, “that every plate had an intensity of its own,
which exercises during a certain exposure a maximum action and that
a deviation to either side from this maximum point, reduced the bene-
ficial applied energy.” The great amount of material observed by him
confirmed the existence of deviations from the law of reciprocity, but
Abney was unable to arrive in his fundamental work at the formulation
of a law of density adjustable to these conditions, which only later was
done by K. Schwarzschild and E. Kron.

Sir William de Wiveleslie Abney (1843-1920) was until 1877 in-
structor in chemistry at the military school in Chatham; from 1877 he
was active in London in the Department for Science and Art. From
1900 he was director of secondary education for England and Wales
and a member of the Royal Academy of Sciences, London. He occu-

SENSITOMETRY

455

pied himself a great deal with photography, photochemical processes,
the chemistry of photographic developers and intensifies, photometric
investigations of the law of density of photographic plates, and spectro-
analytical work. Important are his experiments on solarization and the
connection of exposures and the intensification of photographic silver
bromide gelatine plates.

Abney photographed on specially prepared silver bromide collodion
plates the infrared of the solar spectrum, with new Fraunhofer lines up
tO 2,700 (i(A.

We owe to him the first practical directions for the production of
light-sensitive emulsions. In 1877 he invented copper-bromide silver-
nitrate intensification for the wet collodion plates, introduced in 1880
hydroquinone as a developer for dry plates, and furnished the basis for
the production of aristo paper. Abney was for years president of the
Royal Photographic Society, London.

For a biography and a portrait of this excellent scientist, to whom we
are indebted for much of the most valuable work in the field of photo-
chemistry, spectroanalysis, and photography see Phot. Jour. (1921,
p. 44; also ibid.., p. 29), the exhaustive biography by Chapman Jones,
and the Annual Report of the Smithsonian Institution (1919, pp. 531-
46).

schwarzschild’s law of density

The astronomer Karl Schwarzschild, in 1900, first stated the law,
called after him, governing the density of photographic plates. The
photographic action of light on silver bromide plates depends upon the
product “It p ,” where “I” is the light intensity, “t” the time exposure,
and “p” a characteristic constant for the particular plate; “p” is in gen-
eral less than “I.” If p equals one, we have the simple reciprocity rule.
Later investigations, carried out at Schwarzschild’s suggestion by his
assistant E. Kron, resulted in a more precise formula, based on the
absolute light intensities.

Kron’s law stated that for each kind of plate there is a certain light
intensity at which the energy incident on the plate acts most favor-
ably. This “optimal light intensity” is that at which the incident ray
has a greater photographic activity than at any other light intensity
(greater or less). Kron based upon this his strictly formulated mathe-
matical law of density, in which the curve of density, brought into
relation with the logarithm of exposure, is plotted in the form of a

SENSITOMETRY

456

hyperbola or a catenary curve. In Kron’s law the condition is taken
into account that Schwarzschild’s exponent “p” becomes variable by
very great light intensity, while the time scale is accepted as invariable.

Karl Schwarzschild was born in 1873 in Frankfurt a.M., studied in
Strassburg and Munich, where he received his doctor’s degree, and
came in 1897 to the Kuffner Observatory, Vienna. While working in
the author’s photochemical laboratory, he commenced his studies in
photographic sensitometry, which led to his law of density. He moved
to Munich, where he joined the university staff in 1899; in 1900 he be-
came director of the observatory and professor of astronomy in Got-
tingen, in 1909 director of the photoastrophysical observatory, and in
1912 member of the Berlin Academy of Sciences and honorary pro-
fessor at the university. He died in 1916 from an incurable disease
which he contracted during the World War.

Obituaries of Schwarzschild can be found in: Quarterly of the As-
tronomical Society (LVIII, 191-209), by Oppenheim, his colleague
at the Kuffner Observatory; Die Naturavissenschaften (1916, No. 31),
written bySommerf eld, his companion during his Munich days; Jahres-
bericht der Deutschen Mathematiker-V ereinigung (1917, XXVI, 56-
75 ) , by Blumenthal, his brother-in-law.

Erich Kron 8 (1881-1917) was educated in Potsdam. He wrote, in
1906, an astronomical dissertation for his doctor’s degree; became as-
sistant and observer at the Potsdam astrophysical observatory where
he carried on, urged and guided by Schwarzschild, his experiments on
the laws of density of photographic plates. Kron’s dissertation on the
theory of density was published in 1 9 1 3 in the Publikationen des astro-
physikalischen Observatoriums in Potsdam ( Vol. XXII) . Kron’s theory
marks great progress in the scientific conception of the photographic
phenomenon of density on gelatine silver bromide. This phenomenon
was investigated further and studied particularly by American scien-
tists (E. Halm, 1915, L. A. Jones, E. Huse, and V. C. Hall, 1926),
whose work may all be traced back to Kron’s investigations. He joined
his regiment during the World War, was first lieutenant in the artillery
on the Western Front, in Flanders, where he fell. Obituary in Astro-
nomischen Nachrichten, 1917, CCV, 223.

Among the publications of the Potsdam observatory are two articles
published by him, one on the light change of the short periodic “XX
cygni”; the other on the law of density of photographic plates.

SENSITIZING EMULSIONS

457

PHOTOGRAPHIC PHOTOMETRY FOR THE DETERMINATION
OF THE BRIGHTNESS OF CELESTIAL BODIES

Professor G. Eberhard of the astrophysical observatory in Potsdam
covers this subject thoroughly in the T extbook of Astrophysics, by G.
Eberhard, A. Kohlschutter, and H. Ludendorff (1931, 11(2), 43 1 -
518). This work also contains a historical review on the work of Fou-
cault and Fizeau. In 1858 Warren de la Rue made comparisons of the
luminosity of the moon with that of Jupiter and Saturn, which were
produced on wet collodion plates. In the same year the astronomer
George Phillips Bond reported at the Harvard observatory, in Cam-
bridge, Mass., his experiences with photographic measurements of
stellar luminosity. He established first that increased exposures not
only increase the density of the photographed stellar disks, but also
the diameter of the disks, which can easily' be measured by the aid of
the microscope. Bond used this in his measurements of the luminosity
of stars.

On the occasion of the proposed photographic chart of the whole
heavens, which was resolved on, as an international undertaking, by
the International Astronomical Congress at Paris in 1887, astronomers
decided to organize their efforts along these lines. This work became
extremely valuable to scientific astronomy.

Chapter LXIV. discovery of color-sensi-
tizing OF PHOTOGRAPHIC EMULSIONS; IN 1873
PROFESSOR H. W. VOGEL DISCOVERS OPTICAL SEN-
SITIZING

The action of the solar spectrum on photographic films was investi-
gated soon after the discovery of daguerreotypy for both iodide and
daguerreotype plates by Herschel in 1840 and 1842, by Draper in 1 842,
and by Hunt in 1843. Herschel found that silver bromide is more
sensitive to green than is pure silver iodide. The physicist Crookes
( 1 85 5 ) , J. Muller (1856), Schultz-Sellack (1871), as well as others,
investigated the behavior of collodion plates toward the spectrum.

All early experiments showed that principally blue and violet rays
(also pigments) acted photographically on daguerreotype plates as

45 8 SENSITIZING EMULSIONS

well as in the other photographic processes with silver iodide, silver
bromide and silver chloride. Red, yellow, and deep green, however,
acted little or not at all; thus, the daguerreotype and the dry collodion
process, as well as the gelatine silver bromide were “color blind.”

This was a great defect in photography and made the “color-correct”
reproduction of paintings, and so forth, very difficult, necessitating the
assistance of hand retouching— good or bad. The introduction of the
theoretically conceived three-color photography was also arrested
at first, because the photographic plates available lacked sensitivity for
the optically active rays.

This defect was remedied by Professor Hermann W. Vogel, of
Berlin, in 1873, by his discovery of color sensitizing with the so-called
“optical sensitizers.” This discovery opened a new era in photography
and raised him to the position of the most important photochemist
of the post-Daguerre period and also the most successful promoter
of the technique of reproduction and scientific photography. He pub-
lished his discovery in a well-elaborated form, quite in contrast to
the treatment of many other photographic inventions, which gave
scientists a great deal of work owing to their incoherent statements.
Vogel’s discovery met with much opposition on its first publication,
and he had to fight before he managed to carry it through. In due time,
however, the importance of Vogel’s epoch-making discovery became
clear, and so we shall devote more space here to a report on his life and
works.

In 1873 Vogel busied himself with experiments 1 on the chemical
action of the solar spectrum on silver iodide, silver bromide, and silver
chloride, having received from the Berlin Academy of Sciences a
small spectrograph for his work. He turned his attention to collodion
silver bromide plates, which occupied at that time the foreground of
interest, and the preparation differed from that of those produced
commercially in England. The trade was chiefly concerned with the
elimination of halation, a defect from which collodion plates suffered;
they tried to overcome it by the addition of various coloring matters.
Stuart Wortley manufactured in England such a collodion dry plate
for the trade, which contained as a preservative rubber, gallic acid,
and uranium nitrate, as well as a yellowish-red dye (corallin), to
prevent the penetration of actinic light through the film and the for-
mation of detrimental light reflections from the glass base. As a matter
of fact, such plates, when used for landscapes, showed little halation.

SENSITIZING EMULSIONS

459

H. W. Vogel observed in 1873 that such plates possessed a greatly
increased sensitivity to the green of the spectrum, which was unknown
until then. With great insight he grasped the significance of this
phenomenon as a specific action, namely, as an increase in sensitivity
by the admixed dye. He observed in the case of corallin that this dye
(which absorbs yellow and green) also sensitizes for yellow and green
silver bromide collodion dyed with it and that green aniline dyes
sensitize silver bromide collodion into the red. Thus Vogel made the
enormously important discovery of the “optical sensitizers” (as he
called them), or as they are mostly called today, “color sensitizers.”
From Vogel’s discoveries developed the new color-sensitive processes
which permit photography with correct tone values and called forth
an essential change in the photography of colored objects. This was
fundamentally important not only for correct-color photography but
also for three-color photography. 2

Vogel published his discovery in 1873 3 and exhibited his first spec-
trum photographs on color-sensitized collodio-bromide plates at the
session of the Berlin Society for the Promotion of Photography,
October 17, 1873. He made comparative exposures with his small
spectrograph in 1874, which confirmed his results of 1873 and fur-
nished the proofs for his extensive dissertation in Poggendorff’s
Annalen. Reproductions of Vogel’s spectrum photography, by which
he demonstrated “the increase of light sensitivity of silver halides for
certain colors by admixed absorption media (dyes)” are in the 1932
ed. of the Geschichte (pp. 638-39). Vogel followed up his discovery
consistently and gave exact data in his article “Ober die chemische
Wirkung des Sonnenlichtes auf Silberhaloidsalze,” in Poggendorff’s
Annalen ( 1 874, CLIII, 218) on the behavior of pure silver bromide,
silver iodide, and silver chloride collodion toward the solar spectrum.
He also described the action of corallin, nephthalene red, aniline red,
aniline green (methylros-anilinpicrate), and aldehyde green. These
interesting and historically important photographs Vogel presented to
the author of this book; they are preserved in the collection of the
Graphische Lehr- und Versuchsanstalt, at Vienna, with Vogel’s mar-
ginal notes, and it is doubtful whether any duplicates are in existence.

The diagrams of the curves of the action of the solar spectrum on
silver halides in the collodion process and the description of the action
of color sensitizers which Vogel published in his early reports, are of
permanent interest; since he used a spectrograph with a thick direct-
vision prism, the action of the ultraviolet solar spectrum is missing.

4 6o SENSITIZING EMULSIONS

Vogel also discovered that cyanine is the most efficient sensitizer for
orange-red in collodion plates, which later was recognized by V.
Schumann as also an effective sensitizer for this spectral region in
gelatine plates.

Vogel’s important discovery was at first looked upon with a great
deal of doubt, for instance, Monckhoven, in Ghent, repeated Vogel’s
sensitizing experiments with negative results. This failure aroused mis-
givings as to the correctness of Vogel’s statements; it was later found
that Monckhoven, who had at his disposal more powerful spectro-
graphs, with greater dispersion, had worked with weak spectra, so that
the action of the color sensitizers known at that time, which were not
very strong, was not very prominent, while they showed plainly in
Vogel’s small direct-vision spectral apparatus, used in strong sunlight.

Carey Lea also achieved no better results when working with colored
glass plates in repeating V ogel’s sensitizing experiments . 4 V ogel entered
into various controversies with Monckhoven, Lea, and Spiller, in which
he defended the correctness of his statements ( Phot . Mitt., Vol. XI).

The first who came to Vogel’s assistance with his endorsement was
the famous French physicist E. Becquerel ( Compt . rend., 1874,
LXXIX, 185), who, following along the lines of Vogel’s theory on
the connection of light absorption with the sensitizing of silver bromide
collodion dyed with chlorophyll, found even more sensitivity bands.
This ended the controversy in favor of Vogel.

H. W. Vogel’s AZAL1NE PLATES (1884)

In his experiments with new dyes Vogel came across quinoline red,
discovered in 1882 by Dr. E. Jakobsen, of Berlin, which is a splendid
fluorescent basic dyestuff (from quinaldine and iso-quinoline). This
dye was recognized by H. W. Vogel (1884) as an excellent sensitizer
for green silver bromide emulsions. In itself quinoline red offered no
advantages as a green sensitizer over the acid eosin colors. But it pos-
sessed the important property that it could be mixed without decom-
position with the likewise basic quinoline blue (cyanine equals quino-
line blue), and so it made possible a harmonious sensitizing for green,
yellow, and orange. Thus, Vogel became the creator of the first pan-
chromatic plate. He called this dye mixture “azaline” (Phot. Mitt.,
1884, XXI, 50, 60, 106) and offered it on the market, keeping his
formula secret.

Professor Vogel visited Vienna in 1884 and brought some of his

SENSITIZING EMULSIONS 461

azaline plates with him, where at the Lowy studio, in the preseice of
J. Lowy and the author, he successfully photographed painting "with
the aid of strongly yellow-sensitive glass plates, in which negatives the
red-orange was splendidly reproduced. This was rightly esteened a
great progressive step. 6 The developer, used at that time excluively,
was iron oxalate. The acid reaction of this developer destroyed tie red
sensitivity of the sensitizer (as was later found out, it containel cya-
nine), and it acted as a desensitizer in the development, therefore the
negatives were clear. This first “panchromatic” plate was discussed by
the Vienna Photographic Society and aroused a desire to discover the
secret of its preparation. Dr. F. Mallmann, an amateur photogiapher,
succeeded in this, in company with the professional photographer
Charles Scolik, who reported to Vogel an offer from the United
States, which expressed the desire to introduce his azaline there and
promised large orders for the dye in solution. Vogel sent it to the
United States, from where it was returned to Dr. Mallmann at Vienna;
he had it analyzed in Berlin, where it was disclosed as a mixture of
quinoline-red with cyanine (proportion 10:1); they then published the
composition in photographic circles (Phot. Korr., May, 1886, pp. 331,
337) 37 2 ; see also Vogel, Phot. Mitt., 1886, Vol. XXIII, and the report
of the session of the Society for the Promotion of Photography, Berlin,
September 17, 1886).

This, of course, greatly interfered with Vogel’s exploitation of his
invention, but the azaline solutions sold on the market found, not-
withstanding, many kinds of application.

Not only were these azaline plates used in the reproduction proc-
esses but they also enabled the spectrum analyst, Professor Heinrich
Kaiser (then at the technical college, Hanover) and Professor Runge
to photograph from the red to the green spectral regions in their in-
vestigations in the bands of the spectra of alkalis and alkaline earths in
1888 and later. Lippmann, in Paris, also used azaline for sensitizing the
dry plates used in his interference-photochromy. Azaline plates were
also used in three-color photography.

Of course, azaline plates had their shortcomings, for they were
feebly sensitive, less stable, and required strong light filters in order
to subdue the blue. Nevertheless, azaline presented a remarkable pro-
gress; but it could not compete in orthochromatic photography with
erythrosin and with the new sensitizers of the isocyanine series found
by Miethe and E. Konig. 0

462 SENSITIZING EMULSIONS

BIOGRAPHY OF H. W. VOGEL 7

Hermann Wilhelm Vogel was bom March 26, 1854, and was des-
tined to be a merchant. Having left school at 14, he worked for awhile
in his father’s store and as a clerk in Berlin and elsewhere. His desire
to devote himself to the natural sciences after acquiring an education
was opposed by his father, who saw no financial returns accruing to
his son from science and refused him also the chance to become a
mechanic. His father finally gave up all hope for him and allowed him
to become a cabin boy on a boat. Fortunately, the young man became
too ill to depart, for the whole crew perished from yellow fever during
the voyage.

In the meantime he sought to enlarge his knowledge by reading and
study, and finally, through the kind intervention of a friend, he re-
ceived the parental consent to attend the trade school at Frankfurt on
the Oder. He passed his examination so satisfactorily that he received
a government scholarship of 600 talers to cover his expenses at the
trade institute at Berlin. He moved to Berlin on March 2, 1852, studied
chemistry and physics, and broadened his education in many directions.
His examination paper was so successfully elaborated that it was pub-
lished in Poggendorff’s Annalen der Physik. After a short term of
employment in a sugar refinery, Vogel became, in 1858, scientific
assistant to Professors Rammelsberg and Dove, in Berlin, and in 1865
assistant at the mineralogical museum of the University of Berlin. Here
he began his activity in photography, when required to reproduce
enlarged rock sections. In 1862 he visited the World Exposition in
London, 8 and in 1863 he received his doctorate for a dissertation
Vber das V erhalten des Chlorsilbers, Bromsilbers und Jodsilbers in
Licht und die Theorie der Photographie (Berlin, 1863). In 1864 he
invented his test for silver, that is, titration with iodide of potassium
solution and starch paste as indicator.

In 1863 he founded the Photographic Society, at Berlin, from which
started in 1869, under his direction, the Society for the Promotion of
Photography. From which also sprang in 1887, the German Society
of Friends of Photography, and in 1889 the Free Photographic
Union, both at Berlin. Vogel’s activities in societies were always brisk
and many sided, but also controversial and hostile, involving him in
many disputes. Vogel was also a charter member of the German
Chemical Society (1867) and of the Union for German Applied Art
( 1878) . In 1864 he founded the Pbotogr. Mitteilungen, a leading tech-

SENSITIZING EMULSIONS 463

nical journal, which he edited until his death, after which it lost its
importance. He also founded and directed a photographic laboratory
at the Royal Trade Institute, Berlin, in 1864; when this was merged
with the Technical College, in 1879, Vogel became ordinary professor
of photochemistry and taught spectrum analysis 9 and principles of
illumination in addition to scientific and applied photography.

Vogel was director of the first Berlin Photographic Exhibition,
1 865, 10 also of the Berlin Jubilee Exhibition, 1889; he was also one of
the judges of awards in the World Exposition at Paris, 1867, Vienna,
1873, Philadelphia, 1876, and Chicago, 1893. He visited America four
times; the first time in 1870 as guest of the National Photographic
Association, of which he was an honorary member; in 1893 he attended,
upon invitation, the Photographic Congress in Chicago. Vogel par-
ticipated as photographer in the North-German solar eclipse expedi-
tion to Aden, in 1868, to Sicily, in 1870, with the British expedition,
in four editions, 13 and many of his articles were translated into foreign
expedition, in 1888, to Jurgewetz on the Volga. 11

His scientific activities were many-sided and prolific; his most im-
portant success, the color-sensitizing of photographic films, is dealt with
in detail at the beginning of this chapter. The results of his investiga-
tions are reported in numerous separate publications, particularly in
the Photogr. Mitteilungen . 12 His Handbuch der Photographie appeared
in four editions, 13 and many of his articles were tranlated into foreign
languages.

Vogel’s services to photographic chemistry must be especially em-
phasized; he introduced the paper scale photometer, 14 which retains
its importance today for its practical usefulness, particularly for carbon
and pigment printing. He always stressed the use of the tube photom-
eter, improved it, and was the first to recommend the Durning mag-
nesium ribbon, which is so similar to daylight, with the use of a white
reflecting paper surface as an indirect normal light source ( Handbuch ,
1930, Vol. 111(4), “Sensitometry”).

During ten years, 1867-76, Vogel endeavored to obtain legal pro-
tection for photographs, which at times occupied him to the exclusion
of everything else; his efforts were finally crowned with success by
the German copyright law, which became effective July 1, 1876. He
was always a follower and a lively defender of artistic photography.
He received many honors, among them, in 1894, the gold medal of
the Vienna Photographic Society.

4 6 4 SENSITIZING EMULSIONS

Overwork caused Vogel to suffer from insomnia in his early years,
and he was one of the first on whom Oscar Liebreich experimented
with chloral hydrate, the soporific effect of which was discovered in
1 869. In later years his suffering from lack of sleep made him irritated
and suspicious, which tended to drive him into solitude. He suffered
from diabetes from 1 886 and died from an attack of influenza December
17, i898. 16

His son, Ernst Vogel, who had collaborated with his father in the
field of graphic arts, became his successor in some respects; he con-
tinued along the lines which his father had established.

Ernst Vogel, bom July 23, 1866, at Berlin, studied chemistry at
the technical college in Berlin, devoted himself entirely to photo-
chemistry, and was assistant to his father at the photochemical labora-
tory of the technical college ( 1 890-9 3 ) . He received his doctor’s degree
from the university at Erlangen, in 1891, for his thesis: Beziehungen
zwischen Lichtempfindlicbkeit und optischer Sensibilisation der
Eosinfarbstoffe. On October 31, 1889, he applied for a German patent,
which was granted in 1890 (No. 53078) for the use of collodion and
gelatine films as substitutes for glass as a carrier for sensitive films. After
having acquired during 1892 the necessary experience and practical
training in New York in the plant of William Kurtz (a dear friend of
his father’s), he took an important part in the development of the
three-color halftone process and, with Georg Biixenstein, founded
in 1893 an establishment for photoengraving at Berlin, with particular
attention to the practical application of his knowledge of color print-
ing.

Ernst Vogel was editor of the Fhotogr. Mitteilungen from 1 899 until
his death, August 27, 1901. 10

WATERHOUSE DISCOVERS THE SENSITIZING EFFECT OF EOSIN

Major J. Waterhouse, of Calcutta, made the important discovery in
1875 of the sensitizing action of eosin on silver bromide collodion dry
plates in the green region of the spectrum. He published his findings
in the Brit. Jour. Phot. (1875, p. 4 50; 1876, p. 23, 233, 30 4 ), as well as
in the Phot. Mitt. (1876, XII, 17).

J. Waterhouse was born in England, June 2 4 , i 8 4 2, and died Sep-
tember 28, 1922, a major general. This prominent scientist spent
nearly forty years of his life in the army in India, being for some time
chief of the Cartographic Service at Calcutta. In the eighties and nine-

SENSITIZING EMULSIONS

465

ties he visited Carlsbad, where he took the cure; he always visited Vi-
enna on such trips. Here he met the author of this history and justified
the latter’s respect and admiration for this noted scientist’s knowledge
of and service to photography. He contributed many valuable articles
to the Jabrbucb fur Photographie. Waterhouse returned from India
in 1897 and became president of the Royal Photographic Society,
London. His investigations in the field of photography we have re-
ported elsewhere. In 1868 he worked on a photographic transfer proc-
ess, studied in 1875-76 color sensitizers with the spectrograph and was
the first in 1 894 to start and carry out the three-color process of gravure
printing in India.

DUCOS DU HAURON EMPLOYS COLOR SENSITIVE PLATES FOR
THREE-COLOR PHOTOGRAPHY, 1 875

It is most remarkable that Vogel’s discovery of photographic color
sensitizers were first utilized in photographic practice, not in Germany,
but in France. The French scientists Ducos du Hauron and Cros an-
ticipated the progress in the manufacture of light-sensitive plates with
their ideas on three-color photography.

Louis Ducos du Hauron, born in 1837, in France, to whom is due
great credit for the progress of three-color printing, applied himself
successfully to the introduction of color-sensitizers into photographic
practice. Hauron had interested himself in photography since 1859,
when he tried to produce photographic images in series and invented
a kind of cinematograph, which he protected by French patents of
March 1 and December 3, 1864. He recognized even then the impor-
tance of the principles underlying three-color photography and ap-
plied, on November 23, 1868, for a patent on a photographic three-
color process.

This process of Ducos du Hauron necessitated the making of three
matrices, which were produced on collodio-silver bromide plates be-
hind colored glass (filters), and which were supposed to reproduce not
only the blue and the violet but also the yellow, red, and green of the
original; it was only partly successful. This required plates which were
very sensitive to green, yellow, and red, which were not available until
after Vogel’s discovery of optical sensitizers (1873), of which Ducos
du Hauron soon made use. Ducos du Hauron dyed his plates according-
ly and reported on September 6, 1875, to the Agricultural Society of
Arts and Sciences that he used chlorophyll; Edmond Becquerel ( 1 874)

SENSITIZING EMULSIONS

466

had indicated its sensitizing effect for the red end of the spectrum. He
also used Vogel’s corallin as green sensitizer.

The brothers A. and L. Ducos du Hauron published in 1878 a
pamphlet Photographie des couleurs. They phrased their directions for
producing photographs behind green or orange colored glass filters
as follows. 17 They stated that brominated collodion with eosin, as
recommended by Waterhouse, permitted much shorter exposures than
with chlorophyll and corallin, and gave a detailed description of their
procedure. It consisted in salting the collodion with cadmium bro-
mide, dyeing it with eosin, and then sensitizing it in a silver nitrate bath.
The exposed plate was developed with iron sulphate. The history of
three-color photography and the part which Louis Ducos du Hauron
played in this process, as well as the invention of anaglyphs, is described
in Chapter XCIV. We must mention here only that the work of this
meritorious scientist had also a great influence on orthochromatic (cor-
rect-color) photography.

Chas. Cros 18 also published studies on the classification of colors and
the means for the reproduction of all tones by three negatives (corre-
sponding to red, yellow, and blue).

ADOLPH BRAUN EMPLOYS WET EOSIN SILVER COLLODIO-BROMIDE
PLATES FOR CORRECT-COLOR TONE NEGATIVES OF ART SUBJECTS

The first who used these new wet eosin collodion plates, with acid
iron sulphate developer, for the orthochromatic reproductions of
paintings in color (for monochrome photography, in particular for
pigment printing), was the Frenchman Adolph Braun at Domach
(Switzerland), who worked this process as early as about i878. 1b His
son, Gaston Braun (born 1845), who later became the head of the
firm of Adolph Braun & Co., of Dornach and Paris, devoted himself
from 1869 to experiments with three-color photography after the
methods of Cros and Ducos du Hauron. He used the bromide collodion-
bath process, dyed his plates with eosin, and developed them with acid
iron sulphate for the reproduction of oil paintings (1878), using not
the ordinary eosin, but ethyl eosin, which is more advantageous. In
1878 Gaston Braun reproduced for the first time with such orthochro-
matic collodion-bath plates the paintings in the galleries of Madrid and
St. Peterburg. Their correct reproduction of the tone values of the
yellow and blue excited the astonishment of the professional world.

Gaston Braun photographed, in 1880, many paintings in the museum

SENSITIZING EMULSIONS

467

of the Hermitage at St. Petersburg, where he compared the superiority
of the reproductions made with eosin silver bromide collodion-bath
plates and the inferior results obtained by the old silver iodide wet
collodion process. One of Braun’s earliest reproductions is Gerard
Dow’s painting “The Reader,” at the Hermitage Museum, which he
made in 1880 with dyed bromide collodion, separate silver bath, and
developed with acid iron sulphate developer.

On account of his complete silence about his method, however, none
of those viewing Braun’s reproductions had the idea of applying color
sensitizers in practice for obtaining orthochromatic negatives, because
it was believed that the superior effects obtained by Braun were due
to the use of special bromine salts in his negative collodion. The art firm
of Braun & Co. achieved their world-wide reputation because they were
the first to introduce the orthochromatic process in the reproduction
of paintings. This was followed at about the same time by Swan’s im-
proved pigment (carbon) process.

h. w. vogel’s and e. albert’s experiments with

EOSIN SILVER BROMIDE COLLODION

H. W. Vogel, the originator of color-sensitizers in photography,
urged by Braun’s performance, turned his attention, later, to the use
of the eosin silver bromide process in obtaining color correct negatives
when photographing colored objects, such as paintings and so forth.
Vogel improved the wet bath process with eosin collodion, for which
he received a prize of 1000 marks from the Society for the Promotion
of Photography, Berlin. In 1884 he published his process, which was
similar to that of Ducos du Hauron, in the Phot. Mitteilungen and
pointed out to those engaged in photographic reproduction the ad-
vantages of this process, which, as we have said, was for many years
employed by Braun of Domach and Hanfstangl of Munich, but was
later displaced by the “isochromatic collodion emulsions” of Dr. E.
Albert.

E. ALBERT EXPERIMENTS WITH SILVER BROMIDE COLLODION
AND ADDITION OF EOSIN SILVER ( I 883 )

Dr. Eugen Albert, at Munich, applied himself with great success
in 1 8 8 3 to the work of making a practical collodion emulsion f or repro-
duction methods; he dyed his silver bromide collodion emulsions with
eosin silver or similar eosin dyes in order to sensitize them for green

SENSITIZING EMULSIONS

468

and yellow and employed alkaline development. Thus he adapted this
method to the modern emulsion process and obtained greater sensitivity.
His results, exhibited at the International Art Exhibition in Munich,
in 1883, were the first to be publicly shown, and they attracted great
approval. It was not until five years later that he offered his emulsion
for sale {Phot. Korr., 1888, p. 251).

The preparation of the eosin silver bromide emulsion itself was kept
a secret by Albert. The method was not established and published until
after many experiments by Dr. Jonas at the laboratory of the Graph-
ische Lehr- und Versuchsanstalt in Vienna, and later 20 by Baron A.
Hiibl, of the Military Geographic Institute ( Handbuch , 1927, Vol.
II, Part 2).

SENSITIZING GELATINE SILVER BROMIDE PLATES

The optical sensitizers discovered in 1873 by H. W. Vogel worked
quite satisfactorily in collodion plates; on the other hand, when used
for gelatine silver bromide plates difficulties arose, because the latter
reacted very little with the color sensitizers known at that time. Vogel
considered this as a definitely unfavorable characteristic property of
gelatine plates, so that he at first doubted whether they could be prop-
erly sensitized by dyes. In 1882 the Frenchman Attout, trading as Tail-
fer and Clayton, found that eosin (sodium salt of tetra-brom-fluores-
cein-natrium) made gelatine silver bromide plates highly sensitive to
green; they took out a patent (French patent No. 152615, December
13, 1882), and offered dry plates prepared in this manner for sale in
1883 -84. In the description of their patent they mentioned not only the
addition of the dye to the emulsion itself, but also the subsequent
bathing of the dry plate in the dye solution with the addition of am-
monia and alcohol. They recognized that the dye combines thoroughly
with the silver bromide emulsions and cannot be washed out. 21

V. Schumann reported, shortly after, that cyanine (already known
as a sensitizer for collodion through Vogel), also made gelatine plates
sensitive to red, and Vogel combined quinoline red and cyanine (for
quinoline blue; see earlier in this chapter).

eder’s orthochromatic erythrosin plate (1884)

Attout’s eosin plates had the disadvantage that in the reproduction of
colored objects they rendered the green too light and the yellow too
dark; Vogel’s azaline plates, while qualitatively better sensitized for

SENSITIZING EMULSIONS 469

the different colors were, however, reduced considerably in total sensi-
tivity by the cyanine in the dye used, which necessitated the use of
very dark yellow filters in order to compensate for the excessive blue
sensitivity and to increase the relative yellow sensitivity.

The author discovered in 1884, while systematically and spectro-
graphically investigating the dyes of the eosin group (the results of
which he published in the reports of the Vienna Academy of Sciences),
that erythrosin (potassium salt of tetraiodo-fluorescein) 22 has an es-
pecially favorable effect in the yellow and green. 23 Accordingly, in
the reproduction of colored objects, the relation between green and
yellow is rendered more correctly with erythrosin than with bromo-
eosin as used by Attout; at the same time the gelatine silver bromide
plates retain their high total sensitivity and can be used either without
or with light-yellow softening filters. He communicated his results
unselfishly to the scientific world 24 and so furnished the basis for the
general use of this sensitizer, which was quickly adopted by all manu-
facturers of dry plates. The first preliminary account by the author
in March, 1884, appeared in the April number of Phot. Korr. (pp. 95,
1 2 1 , 3 1 1 ) , also in number o f August 12, 1884, where the advantage o f
the addition of ammonia for the increase of color sensitivity was men-
tioned.

The experiments were carried on with a large Steinheil spectro-
graph equipped with three prisms, which he was able to procure from
a contribution by the government received through the kind inter-
cession of Professor Emil Hornig, the president of the Vienna Photo-
graphic Society. The well-defined spectrograms obtained in this man-
ner permitted an exact insight into the structure of the sensitizing
spectra. 24

These spectrographs brought out the superiority of the iodo-eosin
(erythrosin) over the ordinary bromo-eosin or the substituted bromo-
eosin. The facsimile reproduction of the first spectrum-photo of the
comparative action of erythrosin and of eosin on gelatine silver bro-
mide plates is on p. 652 of the 1932 ed. of the Geschichte; it indicates
the superiority of the former.

Such erythrosin plates, made after the author’s directions, were
first manufactured in the dry-plate factory of J. Lowy and J. Plener,
at Vienna (1884), and were called “orthochromatic plates”; from this
originate the terms “orthochromatic,” “orthochromatism,” and so forth.

With such orthochromatic erythrosin plates the author produced

SENSITIZING EMULSIONS

470

reproductions of paintings (1884) and probably the first orthochro-
matic photographs of yellowed papyrus of old Egypt (for the “Papy-
ros Rainer,” which Professor Karabacek began to publish at that time) .
These erythrosin negatives were exhibited by him in Vienna (1884).

The first public demonstration in Germany of the excellent results
of the orthochromatic erythrosin plates was made by the author on
the occasion of his lecture before the Society for the Fostering of
Photography and Allied Arts at Frankfurt a. M., September 10, 1884.

The originals were there exhibited alongside the reproductions and
were greatly appreciated. One of the first negatives made was of a
colored embroidery and is preserved in the Technical Museum in
Vienna. 25

Owing to the greatly increased sensitivity of the orthochromatic
plates in the yellow-green spectral region, they showed a relatively
higher sensitivity to candle or gas light, and so forth, and permitted
much shorter exposures than ordinary gelatine silver bromide plates in
everyday photography. This the author first reported on April 23,
1885, to the Academy of Sciences at Vienna and elaborated further on
December 17.

This naturally led to photographs of portraits and interiors by gas
and electric-bulb lights, of which Charles Scolik, in Vienna, made use
in 1886.

Orthochromatic erythrosin plates were soon manufactured in all
dry-plate factories and are still considered the best in this class. It is
well known that normal motion picture negative film is dyed more or
less with erythrosin, because this improves the clearness of the image,
aside from the greater sensitivity of the film to yellow-green, in day-
time as well as in electric light, and because the films are very durable.

Later, numerous dyes were investigated for their properties as sensi-
tizers. This information is collected in the Handbuch, 1903, Vol. Ill,
and in Eder-Valcnta’s Beitrdge zur Photochemie und Spektralanalyse
(1904) , as well as in the 1931 edition of the Handbuch.

Erythrosin plates were also found advantageous for photographing
landscapes and clouds, in which field Obernetter-Perufc achieved
great success with their eosin silver plates; they also contained iodo-
eosin (erythrosin). About 1887 the Obernetter dry-plate factory, at
Munich, offered orthochromatic plates with the addition of a yellow
dye for depressing the blue sensitivity; then followed the similar per-
xantho plates of Hauff’s dry-plate factory.

SENSITIZING EMULSIONS

47i

Erythrosin plates are not sensitive to red, which may be overcome
to a certain degree by admixing cyanine; but the effect of this mixture
(of which erythrosin is an acid dye, while cyanine is a basic one), does
not work as well as a mixture of quinoline red and cyanine (Vogel’s
azaline), which are both basic dyes.

E. VALENTA INTRODUCES ETHYL VIOLET, GLYCIN RED FOR RED
SENSITIZERS AS WELL AS WOOL-BLACK (1899)

E. Valenta, in 1899, found ethyl violet to be a splendid sensitizer
for silver bromide collodion in making one of the color negatives of
a color-separation set behind the orange filter. This was accepted ac-
cording to his directions in the industry for the manufacture of emul-
sions, for direct three-color photography and in the three-color half-
tone process on the continent and in England. 28 The clarity and sharp-
ness of the halftone dots of the screen negatives were excellent. The
process worked also with gelatine silver bromide plates. Valenta found
glycine red a good sensitizer, with approximately continuous effect
in green, yellow, and orange red. Jointly with the author he applied
this in photographing the weak spectra of bromine vapor in Pliicker-
tubes with a large grating spectrograph (presented before the Vienna
Academy of Sciences, July 6, 1899); the spectrograms extended far
into the orange red. Valenta wrote on glycine red in Phot. Korr. ( 1 899,
p. 539) and used this dye also for sensitizing the grainless plates em-
ployed in Lippmann’s photochromy process. In wool-black he also
found a red sensitizer sufficiently useful for the conditions of that
period. He published an excellent analysis of the line group A of the
solar spectrum (grating spectrographs) in Eder and Valenta’s Beitrdge
zur Photochemie und Spektralanalyse (1904, table V, 3d part, p. 166) .

Eduard Valenta was born in Vienna, August 5, 1857, studied chem-
istry, and became (1881-84) assistant in the faculty for chemical tech-
nology of organic compounds. Here he wrote his first book, entitled
Die Klebe- und V erdickungsmittel (Cassel, 1884). He worked with
the author on ferric oxalate and its double salts. Then Valenta joined
the chemical factory of F. Fischer, of which he later became director.

Soon after the foundation of the Lehr- und Versuchsanstalt fur
Photographic und Reproduktionsverfahren, now the Graphische Lehr-
und Versuchsanstalt, Vienna, he was employed there, January 1, 1892,
where he remained until 1924, finally as director of the institute. As
head of the photochemical department Valenta found a wide field of

SENSITIZING EMULSIONS

472

activities to which he devoted himself assiduously. The results of his
numerous investigations are published in the Phot. Korr. and in the
Jahrbiicher.

On Valenta’s work covering silver chloride printing-out paper and
silver phosphate emulsions see Chapter LXXIV; on the production of
highly sensitive photographic tracing paper see Chapter LXXVI.

After the publication of Lippmann’s interference— photochromy,
Valenta also occupied himself with this interesting process and col-
lected the results of his work in Die Photographie in natiirlichen Far ben
mit besonderer Beriicksichtigung des Lippmann-Verfahrens (Halle
a.S., 1894). In this he described in detail for the first time the produc-
tion of the “grainless” gelatine silver bromide plates, which were par-
ticularly suitable for the color process. Shortly after Roentgen’s dis-
covery, Valenta, together with the author, published the illustrated
work: Rontgenphotographie. In 1 896 appeared: Behandlung der fur
den Auskopierprozess bestimmten Emulsionspapiere; in 1 898-99 Photo-
graphische Chemie und Chemikalienkunde, now in its second edition.
When the institute was enlarged by the addition of a typographical
department, which brought with it the use of new materials, Valenta’s
activities were extended to the investigation of paper, printing inks,
varnishes, gums, and so forth. These supplied the materials for the
three-volume work Die Rohstoffe der graphischen Druckgewerbe,
which deals exhaustively with the subject and is now in its second
edition. Valenta constructed an apparatus for testing the jellying of
glue, for the examination of the viscosity of collodion, and so forth,
and he designed the viscosimeter named after him. In 1891 he originated
a valuable method of sulphurization, in order to increase the sensitivity
of asphalt in the reproduction processes.

The results of his investigations in the field of photochemistry and
spectroanalysis appeared in collected form in the work published by
Eder and Valenta: Beitrdge zur Photochemie und Spektralanalyse
(Vienna, 1904) andinth t Atlas typischer Spektren (2ded., 1924). Pro-
fessor Valenta was an honorary member of the Vienna Photographic
Society, the Royal Photographic Society, and of many other societies.
He became director (1923-24) of the Graphische Lehr- und Ver-
suchsanstalt when the author retired, and followed him also, after the
author became professor emeritus, as lecturer on photochemistry at
the technical college in Vienna until 1929.

He was the first who investigated, spectrographically and in a syste-

SENSITIZING EMULSIONS

473

made manner, the newly discovered isocyanine sensitizers of E. Konig
(Phot. Korr., 1903, p. 359).

His investigations in the field of the photographic tracing and print-
ing processes, asphalt photography, and so forth are reported more
fully on later pages of this work.

MIETHE AND TRAUBE INTRODUCE ETHYL RED FOR PANCHROMATIC

PLATES (1902)

The new, strong color sensitizers which opened the way for the
manufacture of panchromatic plates, as they are used today, were
found and introduced into practice in 1902 by Professor A. Miethe
and Dr. A. Traube, his assistant in photochemistry at the technical
college in Berlin-Charlottenburg.

Traube proposed to Miethe that in view of the difficulties en-
countered in the use of the early cyanine they should produce other
dyes of this class and test them spectrographically. After having made
a series of experiments for the production of different dyes of this
group, Traube found a readily-crystallizing red-violet dye, which
Miethe and Traube later called “ethyl-red”; this proved to be an
excellent sensitizer for yellow-green up to orange. Neither young Dr.
Traube nor Professor Miethe knew at the time that the chemist Spalte-
holz had anticipated the discovery of this dye, but had not examined
it for its photographic properties and therefore did not recognize them.
Only later, after Traube had manufactured “ethyl-red” (in which
quinaldine was used instead of lepidine), did they learn that this dye
was produced long ago (in 1883, by Spalteholz) and therefore was
not new. Yes, even in the description of the Miethe-Traube patent
an erroneous name of the dye is given. Dr. Konig, in the Phot. Korr.
(1903, p. 578), and the author, in Jahrbuch fiir Photographic (1903,
p. 10), called attention to this misstatement. This German patent
granted jointly to Miethe and Traube on May 6, 1903 (No. 142926),
protected the use of ethyl red as sensitizer of gelatine silver bromide
plates for yellow and orange (with a slight desensitizing action in the
green) ; all this signified a tremendous advance in the manufacture of
color-sensitive plates. The first dry plates sensitized with ethyl red
(dyed in the emulsion) were made by Traube in conjunction with
the dry-plate factory of O. Perutz, in Munich, and sold under the
name “Perchromo-plates-Miethe-Traube.” They probably also added
some quinoline red to compensate for the desensitizing in the green,

SENSITIZING EMULSIONS

474

and still later, as a red sensitizer, the pinacyanol of Homolka, but that
belongs to a later period.

The joint intellectual ownership of Miethe and Traube of this dis-
covery is proved by the patent papers. At any rate, ethyl red opened
new avenues of usefulness in three-color photography.

Adolf Miethe, born April 25, 1862, in Potsdam, studied physics,
mathematics, and astronomy in Berlin, spent some time in the institute
for calculations at the observatory there, and entered, in 1887, the
astrophysical institute at Potsdam in order to study special problems
in the application of photography to astronomical observations. He
concluded his studies in Gottingen, where he published the results of
an investigation on the actinometry of astronomical photographic ex-
posures of fixed stars. In 1891 he became a scientific associate of Pro-
fessor Hartnack, at Potsdam; then he joined the optical works of
Schulze and Bartels, in Rathenow; later he became associate and finally
scientific codirector of the optical establishment of Voigtlander and
Son, in Brunswick. He calculated an aplanat in 1888, and in 1891 in-
troduced the teleobjective a few months after Dallmeyer and Duboscq.
After Vogel’s death he was called, in 1899, to the technical college at
Berlin-Charlottenburg as professor of photochemistry and spectro-
analysis and head of the photographic laboratory and astronomical ob-
servatory. He wrote in particular on the relation of diaphragms and
light dispersion to the image, on astigmatism, and on exposures through
small apertures. With Gaedicke he introduced the magnesium flash-
light in photography, but the flashlight powder recommended by him
was soon abandoned owing to its dangerous explosive composition
( Handbuch , 1912, Vol. I, Part 3).

He became editor of the Photographische N acbrichten when the
Photographic Society of Berlin started that periodical in 1889. He also
edited the Atelier des Photographen published by W. Knapp at Halle.

His greatest achievement was the discovery, made jointly with his
assistant Dr. Traube, of ethyl red as a sensitizer, which permitted in
some measure the production of panchromatic plates. Miethe himself
pursued the practical work necessary. He allied himself with the op-
tician Goerz, in Berlin, who constructed a triple projection apparatus
(Vidal system) for the production of three-color pictures, which pro-
jected the image in full color on a white linen screen (additive method) .
The three-color negatives (exposed behind orange, green, and blue
filters) were made in a special camera, with a rapidly changeable

SENSITIZING EMULSIONS

475

holder, built by Berinpohl; the use of the holder was demonstrated by
the projection of pictures in full color at theaters.

He wrote several works on photographic optics, artistic landscape
photography, three-color photography from nature (1908), and
aerial photography. In 1916 he wrote, with Professor Mente, a text-
book on applied photography, Unter der Sonne Oberdgyptens (2d
ed., 1924).

In 1924 he believed that he had found the secret of transmuting mer-
cury into gold. He had noticed that mercury vapor lamps used for
illuminating purposes, after long use, showed a gray deposit, and he
had been able to isolate traces of gold in this residue. These experi-
ments he made jointly with the chemist Dr. Stammreich in his labora-
tory at Berlin-Charlottenburg. Stammreich carried on principally the
chemical and analytical part of the experiments and actually found
traces of gold in the gray deposit of the lamps. This caused a great sen-
sation, and Miethe was hailed as a successful alchemist. He himself
affixed a memorial tablet in his laboratory at the technical college 27
which stated that here the transmutation of mercury into gold took
place, for he was convinced of the inviolability of his discovery. But
a strict examination by several competent persons demonstrated that
the traces of gold were not formed new from mercury, but were
contained in the mercury at the start and had collected in the gray
deposit of the mercury lamps. Miethe was convinced of the trans-
mutation up to his death and suffered severely from the general scien-
tific rejection; he seldom appeared in public in the last years of his life
and died at Berlin, after a severe illness, May 5, 1927.

Arthur Traube, born March 8, 1878, in Berlin, studied chemistry
at the technical college in Berlin, worked with Professor Miethe, and
received the degree of doctor for his Photochemische Schirmwirkung,
which he worked out in Dr. Miethe’s laboratory. He became first
private assistant and later first scientific assistant to Dr. Miethe. Their
joint work on ethyl red was carried on in 1902. In 1904 Traube
managed the technical department of the dry-plate factory of O.
Perutz, in Munich; he perfected at the same time the first panchro-
matic plates, sensitized with ethyl red. After his return to the Char-
lottenburg technical college in 1905, he developed the fotol print
process, according to suggestions given by A. Tellkampf. After this
followed his work on color photography, from which originated first
diachromy, much later uvachromy, and then uvatype. In 1910 he re-

476 SENSITIZING EMULSIONS

tired from the technical college, established his own photochemical
laboratory, founded in Munich the Uvachrome Company, and incor-
porated it in 1922, of which company he is still the manager (1933).

MODERN COLOR SENSITIZERS OF E. KONIG, HOMOLKA, SCHULOFF, AND
OTHER CHEMISTS AT THE HOCHST DYE WORKS; CONFISCATION OF THESE
PATENTS IN FOREIGN COUNTRIES

Ethyl red was soon outstripped by entirely new dyes, which Dr.
Ernst Konig produced at the dye works of Meister, Lucius and
Briining, of Hochst a. M., as it was called then, and introduced to the
trade as superior, while Miethe and Traube worked in vain to broaden
the sensitivity band of their emulsion towards the red by changes in
the amount of the alkyl in the employed alkyl iodide. Konig accom-
plished this result by the introduction of auxochrome groups in the
benzene nucleus of the quinoline bases. Thus originated the famous
and still unexcelled color sensitizers for green, yellow beyond orange
to red and far into the infrared, which have become indispensable aids
in orthochromatic photography, especially in the field of three-color
photography. We mention here the first sensitizers produced by Konig:
orthochrome, pinaverdol, pinachrome, pinachromviolet (with Stahlin) ,
and dicyanine (with Philips). We cite also pinacyanol, a prominent
red sensitizer, produced by the chemist Dr. Homolka in 1906 at the
Hochst Works, then pinaflavol, a green sensitizer produced by Schuloff
in 1919. Scientific photography, spectrography, and aerophotography
also derived great advantages from these new sensitizers.

In addition E. Konig produced pure filter dyes (among others filter
yellow and pyrazol yellow, 1908) and devoted himself to the inves-
tigation of desensitizers discovered by Liippo-Cramer.

Ernst Konig was born in Schleswig in 1869, was employed by the
Hochst Works in 1893, where he worked for thirty-one years and
established a photographic department. He invented pinachromy by
leuco bases and introduced “pinatype,” invented by Didier, into
practice. He died October 29, 1924, after a long illness, which he con-
tracted in his work with injurious substances soon after the French
occupation of the Hochst Works ended. The author wrote a full
biography of Konig in the Chemikerzeitung (1924, p. 905).

Konig edited a new edition of Vogel’s Photocbemie (1906), then
out of print, which unfortunately he did not complete; He published
Farbenphotographie; the first edition appeared in 1 904, and there were

SENSITIZING EMULSIONS

477

three later editions; finally Autochromphotographie (1908) and Ar-
beiten mit farbenempfindlichen flatten (1909).

Before the World War practically all sensitizing dyes were produced
and sold by the great German dye works, especially by those in Hochst
a. M. When it became more and more difficult during the war for the
Allied nations to procure sensitizers, it became necessary to imitate
the German dyes or approximate them in Great Britain, France, and
the United States. This was attempted by confiscating the German
patents and producing the dyes after the patented formulas and de-
scriptions, as well as from systematic analysis of the original German
dyes. W. H. Mills and W. J. Pope reported this in 1920 to the Royal
Photographic Society of Great Britain (Phot. Jour., 1920, p. 183),
enumerating the German patent papers covering such investigations.
The patent rights having been declared enemy property by the govern-
ment and the German patent rights voided, Mills and Pope furnished
sensitizers to the English dry-plate factories. What they called “pina-
chrome,” however, was not new, but corresponded with a dye made
before the war by the Hochst Works especially for Wratten and
Wainwright, in Croydon, and exported for them to England (from
p-ethoxyquinaldinium iodide and p-methoxy quinolinium iodide with
one ethoxy and one methoxy group) , 28 whereas the dye for Germany
and shipment from Germany under the name pinachrome was always
the dye with two ethoxy groups. Pope himself admitted that some of
his dyes were identical with those obtained formerly in Germany
{Phot. Korr., 1920, p. 313).

In the scientific laboratory of Lumiere, at Lyon, H. Barbier also
investigated isocyanine dyes which contain the diethyl- or dimethyl-
amido groups (Bull, de la Soc. chim. de France, 1920) . But the French
chemist evidently was not aware that a dye of this group had been
produced and sold on the market by the Hochst Works under the
name “pinachromviolet” as a good red sensitizer, which Dr. E. Konig
pointed out in Phot. Korr. (1920, p. 313; see also Wentzel, Handbuch,
1930, Vol. Ill, Part 1).

The great value of these red sensitizers (pinacyanol, pinachrom-
violet, and others) is that they enable aerophotography through fog
and atmospheric haze ; they also play an important part in astronomi-
cal and spectroanalytical photography; also in moving picture photog-
raphy by artificial light.

It should be mentioned here that in 1925 the Eastman Kodak Re-

478 DISCOVERY OF DESENSITIZING

search Laboratories, in Rochester, discovered the sensitizer neocya-
nine, which sensitizes from the red far into the infrared. The I. G.
Farbenindustrie, in Berlin, found rubrocyanine 20 in 1928, and in 1929
allocyanine and other sensitizers for the red and infrared.

Chapter LXV. discovery of desensitizing

The photochemists of the nineteenth century held the opinion that all
substances which annihilate or greatly diminish the light sensitivity
of silver bromide, etc., destroy also the latent photographic image,
resulting from exposure and normally capable of development. It was
not until 1901 that Dr. Liippo-Cramer (Phot. Korr., July, 1901) found
that certain developers of the paramidophenol class, as well as ferrous
oxalate, greatly reduce the sensitivity of unexposed silver bromide,
without destroying its capability of developing the latent image. This
action of certain organic developer solutions which reduces the light
sensitivity was investigated later also by the brothers Lumiere and A.
Seyewetz, in Lyon, 1907. 1 But it was only the discovery of dyes which
were able to act as “desensitizers” in the above-mentioned manner
which led to a revolutionary change of the developing process of
photographic plates by diffused light. This was of the greatest im-
portance for the use of color-sensitized plates. For this discovery we
are indebted to Dr. Liippo-Cramer (at that time in Munich), who,
on the basis of certain theoretical hypotheses, found desensitizers in
the coal-tar dyes of the safranine and related groups, which acted
much more satisfactorily in practice than did the oxidized developer
substances.

Liippo-Cramer’s first article on desensitizing by dyes appeared in
the Swiss periodical Die Photograpbie (October, 1920, Nos. 10-11)
and in the Phot. Korr. (December, 1 920, p. 3 1 1 ) . The first-mentioned
carried the title “Ein neues Verfahren, hochst-empfindliche und selbst
farbenempfindliche Platten bei gewohnlichem Kerzenlichte zu ent-
wickeln.” This method, so surprising in its extraordinary simplicity,
of undertaking development without the slightest danger of fog in
very clear yellow light, consists in either adding to the developer a
solution of safranine dye (phenosafranine, a red dye of which the
homologues, in particular safranine T, are used considerably in the
textile industry) or by immersing the plate before development in a

DISCOVERY OF DESENSITIZING

479

bath containing the dye in solution. Methylene blue was also recog-
nized by Luppo-Cramer as a desensitizer which acts when enormously
diluted, but causes fogging. Luppo-Cramer published his investigations
collectively in his book Negativentwicklung bei hellem Licbte; Sa-
franinverfahren (Leipzig, 1921, 2d ed., 1922). Safranine dyes the
silver bromide grain and acts as a desensitizer, or as it was called later,
a “narcotic.” Safranine proved its value, and Liippo-Cramer’s process
excited the greatest attention in technical circles, because it was a
basic step forward in the developing process, which had remained as
a whole unchanged for forty years. Since the process was given free
to the world and not patented, it was soon used everywhere.

Liippo Hinricus Cramer (1871-1943), who writes under the pen
name “Luppo-Cramer,” was born in East Friesland. He studied natural
sciences in Munich, 1890-91, in Heidelberg, 1891-92, and in Berlin
1 892-94. He received his doctor’s degree in chemistry in 1 894, under
Emil Fischer, for his thesis on substitution products of caffein. He was
employed as chemist with the firm of Schering, in Berlin, from 1894
to 1901, at first in the general scientific laboratory and after 1895 in
their new photographic branch in Charlottenburg. During this period
he attended also the scientific-photographic lectures and laboratory
work under H. W. Vogel at the technical college at Charlottenburg.
He found at this time that the halogen substituted polyphenols were
specially energetic developers, which led to the introduction of bromo-
and chloro-hydroquinone under the trade name “Adurol” ( Handbuch ,
III (2), 1 21). From 1902 to 1918 Luppo-Cramer was manager of the
dry-plate factory of the Dr. C. Schleussner Co. at Frankfurt a.M., and
in 1918-19 temporarily in the war industry in the chemical factory
Griesheim-Elektron. From 1920 to 1922 we find Luppo-Cramer as
technical director of the dry-plate factory of Kranseder & Co., at
Munich. It is there that this scientist discovered, in 1920, the process of
developing in broad daylight with the use of desensitizers.

Liippo-Cramer’s technical publications in periodicals number already
(1932) more than seven hundred. Some collected works must be
mentioned: Photograpbische Probleme (1907); Kolloidchemie und
Pbotograpbie (1908) ; Kolloides Silber und die Photobaloide von Carey
Lea ( 1 908 ) ; Rontgeno graphie ( 1 909) ; Das latente Bild ( 1 9 1 1 ) ; Nega-
tiventwicklung bei hellem Licbte (1921); “Grundlagen der photo-
graphischen Negativverfahren” in the Handbuch (1927), Vol. II (1).

In addition to the discoveries enumerated as of practical importance,

DISCOVERY OF DESENSITIZING

480

Liippo-Cramer’s studies, extending over ten years, on the significance
of colloidal chemistry in photographic problems deserve the highest
recognition. Luppo-Cramer is an honorary member of the photo-
graphic societies of Vienna, Munich, and Frankfurt a.M. Since 1922
Luppo-Cramer has been manager of the scientific photochemical lab-
oratory of the German Gelatine Factory Co., in Schweinfurt. He was
called by the faculty of the technical college of Vienna to a professor-
ship in photochemistry, but declined in order to maintain his position
in the photographic industry.

In competition with phenosafranine, found by Luppo-Cramer,
the “basic scarlet N” was produced by French photochemists (1925),
but it turned out that this dye contained safranine ( Jahrbuch , XXX,
645 )-

Worthy of mention also is the discovery by Zelger, at the Pathe-
Cinema laboratory, Paris, of “protective dyes” against fog-creating
desensitizers. For instance, the strong fog-producing, desensitizing
dye, methylene blue, becomes through the addition of acridine yellow
a desensitizer free from fog, which, however, is not so effective as
pinakryptol-green (see below) or phenosafranine (see also Liippo-
Cramer’s Phot. Indust., 1925^0. 8).

Phenosafranine, which was the first desensitizing dye recommended
by Luppo-Cramer, answered perfectly as far as its effect as desensitizer
was concerned, but it had the defect that it was difficult to wash out
completely from the gelatine plates, and often there remained in the
gelatine film a troublesome reddish stain, which could scarcely be
removed by washing. Other safranine and azine dyes proved to have
a similar defect on re-examination at the Hochst Dye Works.

Robert Schuloff at the Hochst Dye Works succeeded (1920) in
producing a quite effective and very little colored desensitizer, by the
introduction of a nitro group into the well-known green sensitizer
“pinaflavol” found by him, namely, through condensation of m-nitro-
p-dimethylamido-benzaldehyde with a-picolinium salts. Since, how-
ever, its action was still considerably weaker than that of phenosafra-
nine, other more effective representatives of this group were sought,
by preparing numerous similar combinations. A year after the discovery
of phenosafranine as a desensitizer by Luppo-Cramer, Schuloff suc-
ceeded in finding several almost colorless desensitizers among this
group, which possessed great efficiency as desensitizers and had only
the defect of being difficult to dissolve. One of these new desensitizers

DISCOVERY OF DESENSITIZING 481

was placed on the market in 1922 by the Hochst Works, under the
name proposed by Schuloff, “pinakryptol.” It is noteworthy that to the
commercial article pinakryptol there was added from ten to twenty
percent of pinakryptol-green in order to overcome the tendency of
this desensitizer to retard development.

The numerous examples of this group of desensitizing dyes, to which
pinakryptol also belongs, are the subjects of the German patent of the
Hochst Works, No. 396402, dated May 1, 1922; they are all generally
described by the inventor (Schuloff) as “pinakryptols.”

In the further investigation of desensitizing the chemists Dr. E.
Konig, Dr. Schuloff, and Dr. Homolka searched systematically for
new desensitizers among the collection of dyestuffs in the Hochst
Works. Dr. Konig and Dr. Schuloff engaged in constant and lively
exchange of ideas with Dr. Homolka, whose collaboration they valued
highly, owing to his unusual knowledge and his excellent personality.
On the occasion of a conference between these three scientists Dr.
Homolka offered to put at their disposal a green saf ranine which he
had prepared experimentally in small quantities about sixteen years
before according to the directions of Kehrmann. This dye is identical,
as related by Konig to the author, with an isomer of phenosaf ranine
designated by Kehrmann as “isophenosafranine” and differs from it
only by a different position of an amido group, which is, as mentioned
above, green in color and a good desensitizer. It has the advantage that
it can be easily washed out from the gelatine film. This sensitizer, sold
under the name “pinakryptol-green,” was not protected by a patent.

After Schuloff left the Hochst Works, he continued his work at the
Society for Chemical and Metallurgical Production, in Aussig (Czech-
oslovakia), where he acted as manager of the laboratory. He soon
determined that homologues of isophenosafranine as well as numerous
isomers of phenosafranine and their derivatives possess partly even
better qualities than pinakryptol-green. The Aussig Chemical Society
applied in 1925 for a patent on this invention. In the description of
this patent the information is furnished that the position of certain
amido groups is decisive for both the color and the desensitizing action
of amido phenyl-phenazonium compounds. A particular case of these
groups is pinakryptol-green, found by Homolka, from which the
most effective representative of the desensitizers mentioned in the
patent application of the Aussig Chemical Society differs only by an
additional methyl group.

482 DISCOVERY OF DESENSITIZING

The corresponding German patent application was filed by Schuloff
after leaving the employ of the Aussig Chemical Society and was desig-
nated as “Sch. 79634 of July 24, 1926.”

Pinakryptol-yellow, commercially introduced by the Hochst Dye
Works, is one of the best desensitizers and is distinguished by its almost
complete lack of color in the solution ready for use. It was invented
exclusively by Schuloff, and belongs to the large group of pinakryptols
included by the Hochst Works in a German patent, I 26984 of Decem-
ber 11, 1925, applied for as an addition to patent 396402. The corre-
sponding American application of December 1 1, 1926 was taken out
in the name of Schuloff.

Biography of Schuloff: Dr. Robert Schuloff, born at Vienna, March
25, 1883, studied at the universities of Vienna, Geneva, Innsbruck, and
others as a pupil of Graebe, Wegscheider, and Herzig. He received
his doctor’s degree at Vienna and became assistant to the chemist Paul
Friedlander, the discoverer of thioindigo and of artificial “purple.”
In May, 1908, he was employed by the dye works of Meister, Lucius
and Briining, at Hochst a. M., where he remained until 1922. Here he
worked in the laboratory for dye research and in the central scientific
laboratory, particularly as collaborator of Dr. E. Konig. He found,
independently, the green sensitizer pinaflavol, which comes under the
German patent 394744 of May 23, 1922 (inventor Dr. Robert Schu-
loff). Although the patent application 395666 of the same date in the
name of the factory specifies, for reasons which can only be con-
jectured, that Dr. Konig was the sole inventor, Dr. Schuloff felt justi-
fied, notwithstanding, to consider the invention as his exclusive prop-
erty. The author has also before him the original of a letter from
Konig to Schuloff, in which Konig, in reply to an inquiry from Schu-
loff about the above-mentioned position of the dye works, writes,
among other matters, “that he would take care that the name of Dr.
Schuloff, as inventor, should receive the recognition which was due
him.” About pinaflavol Dr. Schuloff writes:

1 want to add that other representatives of the pinaflavol group deserve
attention. For instance, the combination dimethylamido-benzaldehyde
plus pyranton (i.e., 2-methyl-5-ethyl-pyridin-halogen-alkylate, e.g., ethyl-
ate). This combination is almost equivalent to dimethylamido-benzalde-
hyde plus alpha-picolinium salts (pinaflavol) and can replace it entirely.

Pinaflavol appeared at the end of 1920 as a green sensitizer, the
chemical composition being kept secret by the Hochst Works. Its

DISCOVERY OF DESENSITIZING 483

spectrographic qualities were published almost immediately afterwards
in the technical journals (Phot. Korr., 1920, p. 304; and 1921, p. 29).

Dr. Schuloff writes further:

Finally it is not without interest that the patent for pinaflavol was first
applied for by the Hochst Dye Works, in February, 1921 (F 48516 IV/22),
but the application was withdrawn before publication, because at that
time the patent situation was too uncertain, especially in Great Britain and
the United States, where there was danger of confiscation. Thus it hap-
pened that shortly before the second application, in 1922, there appeared
in the Journal of the Chemical Society an article by Pope and Mills on
the combination: dimethylamido-benzaldehyde plus alpha-picoliniodo-
methylate, in which this combination was hailed as the first specific green
sensitizer. I do not know whether these English gentlemen invented pina-
flavol independently after “pinaflavol” had made its appearance on the
market or arrived at the knowledge by analysis of the constitution of the
commercial dye. In fact, I informed them on my behalf and that of Dr.
Konig that our pinaflavol, which had been on the market for quite some
time before the date of their publication, was identical with the dye
described by them; but they refused to publish an explanation of this
matter in the Journal of the Chemical Society.

It is also of interest to read in a letter from Schuloff to this author
of the genesis of the invention of pinakryptol and many similar desen-
sitizers:

I endeavored, after the discovery of “pinaflavol,” by modifying the pina-
flavol molecule to produce still better green sensitizers and introduced,
among other things, the nitro group in the aldehyde component in the ex-
pectation of changing the specific color of pinaflavol still more towards
the yellow. Much to my surprise, I obtained an almost colorless product
from the introduction of the nitro group into the dimethylamido-benzal-
dehyde, and the combination m-nitro-p-dimethylamido-benzaldehyde
plus alpha-picolin-iodoethylate proved itself, in contrast to the derivate
free from nitro groups (pinaflavol), a strong desensitizer. After produc-
ing numerous derivatives (more than one hundred) the following combi-
nation, m-nitrobenzaldehyde plus beta-naphtoquinaldinium-dimethyl-sul-
phate, finally manifested itself as the most efficient desensitizer, equally as
strong as saf ranine. In spite of its comparatively poor solubility, it was at
first offered for sale as “pinakryptol,” but was displaced later by the fol-
lowing product, which was more soluble: m-nitrobenzaldehyde plus quin-
aldinium salt, which, however, was not as active a desensitizer. A defect
which attached to both products was their property to retard develop-
ment. In order to eliminate this defect or at least to reduce it measurably,

484 DISCOVERY OF DESENSITIZING

I tried to combine them with other desensitizers. The addition of saf ra-
nine brought no desired result, but the admixture of small amount of in-
dulin scarlet, pinagreen, and other dyes was successful. These experiments
also showed that the combination of pinakryptol had a potential effect
with indulin scarlet and with pinakryptolgreen, but not with safranine,
in which combination it had only an additive effect.

At the end of 1923 Schuloff joined the organic chemical scientific
laboratory at the Aussig Society for Chemical and Metallurgical Pro-
duction as manager, and in 1927 established himself at Vienna as con-
sultant chemist, with other associates.

Biography of Dr. Homolka: Dr. Benno Homolka (born in Bohemia,
i860, died in 1925, at Frankfurt a. M.) was a prominent color techni-
cian and photochemist; he was manager of the dye works of Meister,
Lucius and Briining, in Hochst a. M., studied chemistry at Prague and
Munich, was assistant 1882-86 of the famous chemist Adolph von
Baeyer, of Munich, discoverer of eosin dyes and of artificial indigo,
in the preparation of which he participated. He went to the Hochst
Dye Works from here, where he specialized in dye chemistry, but he
devoted himself later to photochemistry. Most of his results were pub-
lished in the Thotographische Korrespondenz, Vienna. Dr. Homolka
came into contact with applied photography by his invention of the
excellent red sensitizer pinacyanol, and the important desensitizer pina-
kryptol-green. He also invented a new photographic printing process,
based on the sensitivity to light of the o-nitrodiaminotriphenyl methane
bases, which was first published in the Handbuch (1926) Vol. IV; he
published there also (on p. 492), articles on pinachromy and on the
chromogenic development of gelatine silver bromide (p. 512). He
set up the hypothesis that the latent silver bromide image is a combina-
tion of silver subbromide and silver per bromide ( Handbucb , 1927, II
(1), 160, 617), wrote on the fog along the edges of silver bromide
plates (ibid., p. 347) and on other subjects.

Only through the introduction of desensitizers by Luppo-Cramer
were the sensitizers for panchromatic and other color-sensitive plates
enabled to reach their full measure of usefulness. Before that invention
the developing of such plates, which could only be done in complete
darkness or under the weakest kind of green light, was surrounded
by great difficulties and very uncertain. Through the use of desensi-
tizing dyes the development of plates or films of the highest color-sensi-
tivity was made easy, so that they are now widely used in the mass
production of motion picture films.

Chapter LXVI. film photography and

THE RAPID GROWTH OF AMATEUR PHOTOG-
RAPHY

EASTMAN-KODAK; GOODWIN

Through the introduction of flexible, light, unbreakable film , 1
amateur photography, travel photography, and motion picture photog-
raphy were greatly advanced. On the road the weight and bulk of
glass plates were extremely burdensome and added many difficulties
to the work; the danger of breakage was undoubtedly another reason
why a more suitable base or carrier for the light-sensitive material was
sought as a substitute. The early “negative paper” employed by Fox
Talbot, later improved in many particulars 2 offered undeniable ad-
vantages, owing to its light weight and small bulk. The “grain” or
structure of the paper, discernible in the prints was discounted as a
small fault and was eliminated later, when stripping films were intro-
duced.

Warnerke, as early as 1875, produced dry collodion silver bromide
films on chalk coated paper, which could be stripped (see Handbuch
1927, II (2), 310). Paper coated with silver bromide collodion, which
could be stripped, by Milmson in 1877 {Phot. Korr., 1877, p. 225)
and by Ferran and Pauli in 1880 {Phot. News, 1880, p. 365) are re-
ported in the Handbuch (1903, III, 593).

E. Stebbing produced a tanned gelatine film base between two col-
lodion layers in order to obtain greater strength and toughness {Brit.
Jour., May 16, 1879; also 1884, p. 30). Wilde, a photographer in
Gorlitz, combined gelatine and collodion layers {Phot. Korr., 1883,
p. 162). G. Balagny, at Paris, combined alternate flexible layers of
collodion, varnish, and gelatine {Moniteur Phot., 1886, p. 9, 20; Phot.
Woch., 1886, pp. 302, 354; 1887, p. 67; Phot. Korr., 1885, p. 98; 1886,
pp. 361,442).

The manufacture of machine-made papers having meanwhile made
great progress, the production of gelatine silver bromide negative paper
(analogous to silver bromide positive paper) was taken up by Morgan
and Kidd (English patent of June 5, 1882), by Warnerke in London,
by Moh in Gorlitz (1897-98), by the Neue Photographische Gesell-
schaft in Berlin, and by others.

The use of celluloid as a film base was patented by Parkes in 1856
as “transparent support for sensitive coating,” but he never was able

4 8 6 FILM PHOTOGRAPHY

to use it photographically. Serviceable celluloid in sheets was first
commercially produced by John W. Hyatt 3 at Newark, New Jersey.
The brothers Hyatt were the first to produce, in 1869, negatives on
semirigid celluloid sheets. Flat films on celluloid sheets, coated with
gelatine silver bromide emulsion, were produced by Fortier and ex-
hibited to the Paris Photographic Society, March 4, 1881, but the films
were imperfect and streaky. Satisfactory flat films on clear celluloid
were produced commercially by John Carbutt, in Philadelphia (1888).
This firm developed the manufacture of flat films on a large scale and
was the first to export films to Europe. Carbutt also used mat surface
celloidin sheets as film carriers..

The Reverend Hannibal Goodwin, an Episcopal clergyman at
Newark and an amateur photographer, applied for a United States
patent on May 2, 1887, on a process which produced a mass, similar to
celluloid for roll films, of suitable collodion mixtures. After prolonged
delay, caused by “interferences” and the filing of new and amplified
specifications, the patent was granted on September 1 3, 1 898 (U. S. P.
No. 610,861). We shall discuss this later in detail.

George Eastman was the pioneer in introducing the manufacture
of roll films into the photographic industry and practice with complete
success. The history of the manufacture of films and the use of roll films
in suitable holders is closely interwoven with his name.

George Eastman 4 was bornjuly 12, 1854, at Waterville, New York,
a very small town with only a few hundred inhabitants. He was de-
scended from an English family who settled in Massachusetts in 1638
and received land grants from the government. There the Eastman
family lived for about two centuries, surviving the attacks of the In-
dians; they belonged to the pioneers of America. The house in which
George Eastman was born was built in colonial style. When he was
six years old his father moved to Rochester, where he conducted a
commercial school. The father died two years later (April 27, 1862),
and the widow and children lived for a time on the income from the
school, but a few years later they met with reverses. The boy had to
leave school when fourteen years old and work for three dollars a
week in an insurance office. As the only son, he assisted his mother in
the strenuous work of running a boardinghouse. Young Eastman
slowly worked his way up in the business world until he earned six
hundred dollars a year, which, at his age, was as much as he could ex-
pect for a long time to come. Later (1874) he succeeded in getting a

FILM PHOTOGRAPHY

487

position in a bank with a salary of $1,400. This, of course, seemed a
great income at that time. He had attained what he had set out to do;
he was now independent and could support his mother. Now came
the decisive change in his life. As he tells the story:

My Chief, whose assistant I was, left the bank. I had done a great deal of
his work and was thoroughly familiar with it. All my fellow workers
shared my expectation that I would be promoted to fill his position. I did
not get it. Some relative of a director of the bank was appointed and put
by my side. It was not just. That was not honest. It mocked all justice. I
remained a short time, then I left. I now devoted myself entirely to my
hobby, photography.

In the beginning Eastman worked with the troublesome wet collo-
dion process, until he read of the new gelatine (silver bromide) dry
plates. In 1877 he experimented in making these plates at home, fol-
lowing the methods of emulsion making found in the English technical
journals. In this he had such success that he decided to start upon a
new career as a dry-plate maker. Beginning in a small factory, he had
worked out in June, 1 879, a dependable formula for the production of
emulsions, and he coated glass plates with them. Then he designed and
built a machine for flowing the emulsion onto the glass plates, and
patented it on July 22, 1879, in England, and on April 1 3, 1880, in the
United States (No. 226503). Good photographs by Eastman made
on such plates in the winter of 1879-80 have been preserved and one is
reproduced in Ackerman’s biography of Eastman. 4 In 1880 he im-
proved this coating machine and thus was enabled to increase the out-
put and the sale of Eastman dry plates very considerably. This necessi-
tated the enlargement of his small factory.

In January, 1881, he associated himself with Colonel Henry Alvah
Strong, in Rochester, who was interested in many industrial enterprises.
Strong invested five thousand dollars in the joint enterprise. The
product of the company was more widely introduced and found larger
sales, until the monthly deliveries of plates were valued at four thousand
dollars. Suddenly the company met with serious difficulties in the
manufacture of their product; the plates suffered deterioration between
factory and user and showed troublesome fog. Eastman and Strong
went to England to seek advice.

Eastman succeeded in being permitted to spend two weeks in the
plate factories of Mawson and Swan, of Newcastle, obtaining there
information and processes which enabled him to remedy the defects

FILM PHOTOGRAPHY

488

which had caused so much trouble. No longer than four weeks after
the threatened catastrophy, manufacturing for the next season’s needs
was again in full swing at Rochester. Eastman had recognized that poor
gelatine has the worst kind of influence on emulsions.

But business battles also had to be fought. When about 1884 the
dry-plate trade in America was threatened by strong competition, it
was necessary to find new ways of getting and increasing business. It
was at this time that Eastman conceived the idea of roll films, which
simplified photography and made it really popular, because it was no
longer necessary to carry heavy plates or plate holders.

Then came paper films, that is the film consisted of paper coated
with an emulsion. In order to make this process possible, it was necessary
to coat the emulsion on long continuous widths of the paper, for which
Eastman invented a special coating machine, which he patented in 1885.
The paper sensitized in this manner was stored in a “roll holder,” which
could be attached to the back of the camera in the same manner as a
plate holder. The “grain” of the paper, however, was so disturbing that
it made paper negative film quite unsatisfactory. It was soon displaced
by the so-called “stripping film,” in which the paper served only as a
temporary carrier for the emulsion layer. After exposure and develop-
ment, the picture could be and was transferred to a glass plate, and the
paper was stripped off by removing an easily soluble gelatine layer
inserted between plate and film. This “stripping film” was patented
(U. S. P. October 14, 1884, No. 306,594).

It now became necessary to invent a mechanism in order to keep the
roll film firmly fixed in the camera in its proper position. For this pur-
pose Eastman employed the camera manufacturer William H. Walker,
who had discontinued his own business and started to work for East-
man in January, 1884. He solved the problem. From twenty-four to
one hundred exposures could be made in a hand camera with such a
stripping roll film. Eastman now planned the establishment of a new
company, which started in October, 1884, under the name Eastman
Dry Plate & Film Company of Rochester. The initial capital was two
hundred thousand dollars. The officers of the new company were
Henry A. Strong, president, J. H. Kent, vice-president, George East-
man, treasurer, and W. H. Walker, secretary.

When the Eastman- Walker holder for roll films appeared, attention
was called from many sides to the older roll film holder of Warnerke
and to the fact that Melhuish and Spencer, at a much earlier date, were

FILM PHOTOGRAPHY

4*9

granted an English patent (May 22, 1854) on a roll-film holder for
Talbotypes. But the mechanism of the Eastman- Walker roll-film
holder was new, well designed for the use of the silver bromide films,
and most generally used.

In January, 1885, the Eastman company started an advertising
campaign on a large scale to promote the sale of the roll holder and
film, and from this campaign dates the introduction of these inventions.
For his handy camera, which combined within itself camera, roll hold-
er, and stripping film, Eastman invented the name “Kodak,” which was
not trademarked in the United States until September 4, 188 8.

On the origin of the word “kodak,” George Eastman lifted the veil.
The word “kodak” was thought out by Eastman himself in 1888, in-
vented out of pure air, and signifies really nothing; it is simply a short,
particularly pregnant trademark, known all over the world; it has
passed even into literature. In American Photography (1924) Eastman,
describing the origin of the word, concludes: “Philologically, there-
fore, the word ‘kodak’ is as meaningless as a child’s first ‘goo.’ Terse,
abrupt to the point of rudeness, literally bitten off by firm and unyield-
ing consonants at both ends, it snaps like a camera shutter in your face.
What more could one ask?”

This first kodak was a box camera equipped with two spools; it
was placed on the market in 1888. The pictures taken with it were
circular and had a diameter of 6.5 cm. (2/2 inches). The first model
of its kind, “Kodak No. 1,” is reproduced in the 1932 German edition
of this History (p. 67 9). 5 The apparatus measured 8 x 9 x 16 cm. (3 x
3 /i x 614 inches), weighed 680 grams (1 '/ 2 lbs.), and contained in the
roll-film holder a strip of film sufficient for one hundred pictures.

Kodak No. 1 was very handy and achieved an enormous commercial
success, owing to its simplicity and its low price. Soon other cameras
followed, of various designs and equipment, with bellows, and so forth.

Stripping films were later displaced by the Eastman transparent films.
These were produced by Eastman and the chemist Henry N. Reichen-
bach, March, 1 889, by dissolving nitrocellulose in methanol with cam-
phor, fusel oil, and amylacetate also present, which gave an entirely
transparent film base. On December 10, 1889, patent No. 417,202 was
granted to Reichenbach by the United States Patent Office, while on
March 22,1 892, and July 19, 1892, two additional patents were granted
to Eastman and Reichenbach. In the summer of 1 889, Edison purchased
from Eastman a $25 kodak, and this kodak was reconstructed by W.

FILM PHOTOGRAPHY

49 °

K. L. Dickson and the Edison staff as the “first Edison motion picture

camera.”

Eastman early observed the electrical discharge phenomena of col-
lodion films (nitro films) ; he tried to eliminate them by the addition to
the support of hygroscopic salts (potassium nitrate or ammonium
nitrate), Eastman patent No. 584,862, which was the first successful
attempt of this kind. Later, backing the film with gum arabic was
recommended or coating the nitro films with a very thin layer of acetyl-
cellulose (Lovejoy, patent No. 1,232,702).

The modem daylight-changing roll-film system was invented by
S. N. Turner, a camera-maker in Boston, who took a patent on it.
Eastman first purchased license under the Turner patent and then pur-
chased the patent outright along with the Boston Camera Co., owned
by Turner, for $35,000. The actual cost to the company, however,
was only $24,100 for the idea of packing the roll film with a backing
of black paper.

According to Turner’s invention, the strip of film was rolled on its
spool in intimate contact with a longer strip of black paper, on the back
of which numbers for each picture were printed, which could be
read through a little window in the back of the camera as the roll was
advanced. These statements' 3 are supplemented by communications
which were sent at the time by the Anthony and Scovill Company in
New York to Eder. 7 According to these letters, Parker B. Cady, an
employee of the Blair Camera Company, invented, about 1 894 or 1 895,
a kind of daylight pack system for roll films, and that kind of celluloid
films were made by the Blair Camera Company for the Boston Camera
Company and introduced by them first on the American market, and in
Europe by the European Blair Camera Company, London. The East-
man Kodak Company later acquired the Boston Camera Company,
but continued the production and sale of their own films, which soon
gained the approval of the public.

The Eastman Kodak Company offered orthochromatic roll films
for sale before the end of the nineteenth century, later “verichrome”
orthochromatic film. “Supersensitive” panchromatic film is another
important product of the company.

In 1895 the Eastman Kodak Company introduced the “pocket
kodak” of Frank A. Brownell, of which the first lot made ran up to
twenty-five thousand. In 1898 a further important progressive step
was taken in the construction of roll film cameras, when folding appara-

FILM PHOTOGRAPHY

tus was constructed. The first of these was called the “folding pocket
kodak”; in 1900 followed the Brownie camera, made especially for
children, which sold at only one dollar. Still lower in price and very
recent was the Hawkeye camera, which could be bought for eighty-
nine cents.

After 1895 the business expanded enormously in the direction of
the flourishing motion picture industry, which brought about the
production of a special positive film for projection. The “non-curling
film,” with a gelatine coating on the reverse side, was made in 1903.
The Eastman Kodak Company also produced before 1909 acetate
cellulose films and others.

The growth of the Eastman Kodak Company seems like an industrial
fairy tale. From a single associate with Eastman, the number of em-
ployees of the company increased to thirteen thousand, and from the
primitive workshop grew ninety buildings. Kodak Park alone, with
its seventy-five buildings, occupies four hundred acres, which does not
include the other plants at Rochester and elsewhere throughout the
world.

In 1912 Eastman installed at Rochester a splendidly equipped re-
search laboratory under the direction of Dr. C. E. Kenneth Mees, who
surrounded himself with many distinguished scientists, among them
Dr. S. E. Sheppard, Dr. Walter Clark, L. A. Jones, J. G. Capstaff, C. J.
Stand, J. I. Crabtree, and A. P. H. Trivelli. Later he established a re-
search laboratory at the Kodak-Eastman Works at Wealdstone (Mid-
dlesex), England, under the direction of Dr. Walter Clark, who still
later joined the research laboratory at Rochester. Their investigations
are published in the Abridged Scientific Publications published yearly.
In addition, the laboratory issues monthly the Kodak Abstract Bulle-
tin, which gives abstracts of all papers of technical and scientific interest
appearing in the United States and foreign countries in the photochemi-
cal field, including all patents. Eastman contributed largely to numerous
scientific and educational institutions and donated nineteen and one-half
million dollars to the Massachusetts Institute of Technology.

Eastman, who never married, was one of America’s greatest philan-
thropists. By 1932 the sum known to have been given by him for
charitable, educational, and other welfare work amounted to one
hundred million dollars.

He surprised the inhabitants of Rochester, New York, with the
gift of a theater with which a musical conservatory is connected. His

FILM PHOTOGRAPHY

492

original gift to this institution was $3,520,000, which he supplemented
a few months later by an additional million dollars for the equipment.
The theater is most beautifully appointed and seats more than thirty-
three hundred persons. There is also a small lecture hall completely
equipped for the exhibition of motion pictures.

Eastman presented more than half his stock in the Eastman Kodak
Company, valued at fifteen million dollars, and seven and one-half
million dollars in addition to the University of Rochester.

Most of the employees of the company are stockholders in the enter-
prise, which increases their own interest in its success and promotes
that of the company. At seventy-one years, Eastman still took an active
and lively interest in the business. In 1925 Eastman retired from the
active management. He left as his principal successors William G.
Stubeer, president, and Frank W. Love joy, vice-president and general
manager. After having given up the presidency, he remained as chair-
man of the Board of Directors until his death, which took place March
14, 1932. The value of Eastman’s estate at this time was $25,561,640,
of which an amount estimated at $19,287,143 went to the University
of Rochester as residuary legatee, making his total gifts to that institu-
tion approximately $35,000,000.

goodwin’s patent suit against the Eastman company

The American clergyman Reverend Hannibal Goodwin (1822-
1900) of Newark, New Jersey, was the first to apply for an American
patent on the production of light-sensitive celluloid strips (flexible
transparent film) , which later became so important in motion picture
photography. This application by Goodwin, dated May 2, 1887, en-
countered “interferences” and was amended in its specifications, so
that it was not granted until September 13, 1898 (U. S. P. No.
610, 86 1 ) - 8

The Eastman Kodak Company, in the interval, had applied for two
similar patents under the name of H. M. Reichenbach, which led to
litigation lasting for years.

The experiments of Eastman and Reichenbach solved . . . the problem of
making, on a commercial scale, transparent nitro-cellulose photographic
Tollable film. December 10, 1889, patent No. 417,202 was granted to Rei-
chenbach by the U. S. Patent Office, while on March 22, 1892 and July
19, 1892, two additional patents were granted to Eastman and Reichen-
bach. (Ackerman, George Eastman, p. 62).

FILM PHOTOGRAPHY

493

Fritz Wentzel writes in Eder’s Handbuch (1930, Vol. Ill, Part 1 ) that
this patent included not only the product but also the process itself,
the underlying principle of which consisted in the introduction into
the solution of a high-boiling solvent for nitrocellulose, which per-
mitted the low-boiling solvent to evaporate first. The high-boiling
solvent held the material moist and in a soluble state until it was com-
pletely evaporated; this prevented the separation of the nitro cellulose.

For more than eleven years the patent suit remained undecided by
the Patent Office and the Federal courts, because the Eastman Kodak
Company during this time employed every possible means to prevent
the granting of the patent to Goodwin. Finally, however, on September
13, 1898, Goodwin was awarded the patent rights (U. S. P. 610,861).
Shortly afterward Goodwin’s patent rights were transferred to the
Goodwin Film & Camera Company, controlled by the Ansco Company
of Binghamton, who acted as plaintiff in the case against the Eastman
Kodak Company. These legal proceedings, unique in the history of
the patent suits of the time, were begun after Goodwin’s death and,
on account of the length of time involved, as well as the unusual amount
of damages assessed, amounting to millions of dollars which the Eastman
Kodak Company paid to the Ansco Company, occupied the time of
the courts until March, 1914, when the final decree was entered in
Goodwin’s favor.

This gave definite recognition to Goodwin as the original and right-
ful inventor of the celluloid base for roll films. Unfortunately, Good-
win had died in 1900, but his wife and son, who survived him and lived
in straightened circumstances, received a considerable part of the finan-
cial award. Goodwin also obtained a number of other patents for the
production of photographic film bases, among them one which applied
the valuable properties of amylacetate to his purpose.

Goodwin was extremely well liked and popular with the members
of his congregation; he liked and enjoyed amateur photography, in
which he also instructed the pupils of his Sunday School. He had a
fairly accurate knowledge of the technical side of photography and
was sufficiently familiar with chemistry to enable him to make his
own experiments. This doubtless led him to the idea of the production
of transparent celluloid films and their use in roll holders as simplify-
ing photographic practice.

His experiments required constant and considerable expenditures,
which he found it difficult to provide and which involved severe de-

FILM PHOTOGRAPHY

494

privations. When the patent suit against the Eastman Kodak Company
entered its more serious phase, it became impossible for him to obtain
the necessary funds to meet the expense. He was forced to assign his
patent rights to the predecessors of the Ansco Company, receiving
therefrom a small amount of cash and a block of stock in the company,
which became very valuable when the courts decided in his favor.
Unfortunately, he did not live to see this change of fortune. The Essex
Camera Club and his church friends erected in the Public Library at
Newark, New Jersey, a tablet to his memory in 1914, with the follow-
ing inscription:

APRIL 21, 1822 DEC. 31, 1900

REVEREND HANNIBAL GOODWIN

A DEVOTED PASTOR

His service in the church covering charges in this state and in
California included the Newark parishes of St. Paul’s and the
house of prayer. He foresaw the possibilities of photography
as an instrument of education and devoted his inventive talent
to the improvement of that art in the rectory of the house of
prayer at Broad and State Streets. His experiments culminated
in 1887 in

THE INVENTION OF THE PHOTOGRAPHIC FILM

As a memorial to the inventor of the device that has proved so
potent an agent for the instruction and entertainment of man-
kind this tablet is erected.

THE ESSEX CAMERA CLUB AND FRIENDS, 1914

The patent suit of Goodwin vs. Eastman had no influence on the
growth of the Eastman Kodak Company, which developed its own
methods and inventions and became the largest film manufacturer in
the world.

Chapter LXVTI. the stroboscope and

OTHER EARLY DEVICES SHOWING THE ILLUSION
OF MOVEMENT IN PICTURES

The silver bromide process made possible the easy production of
instantaneous photographs and the manufacture of photographs in
series and their projection, of which toward the end of the nineteenth
century those made on long celluloid strips achieved the greatest suc-
cess. The beginning of optical presentations of serial pictures reaches
back far into the past.

Here, also, we find presentiments on the part of the early Romans,
who were endowed with a strong sense of imagination. A quotation
from the poetic writings of the Latin poet and scientist Lucretius Carus
(96 B.C.-55 b.c.), De rerum natura (Book V, lines 768-73) was inter-
preted to indicate that he understood the synthesis of serial images. 1
The passage cited reads:

Quod superest, non est mirum simulacra moveri
Brachiaque in numerum jactare et cetera membra;

Nam fit ut in somnis facere hoc videatur imago;

Quippe ubi prima perit alioque est altera nata
Inde statu, prior hie gestum mutasse videtur;

Scilicet, id fieri celeri ratione putandum est.

In translation it reads as follows:

And further ’tis not strange that images
Are moved, and throw about their arms and limbs
In rhythmic order: for in sleep sometimes
An image seems to do so: when the first
Has disappeared, and another comes
In different postures, then the former seems
To have changed its attitude. You must conclude
That this is done with great celerity.

Sir Robert Allison, London, 1919.

This vague statement of Lucretius Carus does not in any manner
detract from the merit of Plateau and Stampfer, the later discoverers
of stroboscopic viewing.

It is noteworthy that Plateau himself was familiar with the fore-
going verse, because he published a note about it which reads, “On
the passage in Lucretius, where it is believed one recognizes a descrip-
tion of the phantascope” (Bibl. univ., 1852, ser. 4, Vol. XX).

496 EARLY DEVICES FOR MOVING PICTURES

The first device for serial pictures and their observation through
stroboscopic viewing was invented by Joseph Antoine Plateau ( 1801-
83), professor at Brussels and later (1835) professor of experimental
physics and astronomy at Ghent. He was a distinguished scientist in
the field of optics, although blind from his thirty-ninth year, a mis-
fortune arising from the eyestrain due to his studies.

Plateau is looked upon as inventor of the so-called “zoescope.” 2 He
published the principle of his phantascope in his dissertation, Sur quel-
ques proprietes des impressions produites par la lumiere (Liege, 1829),
but he gives the date of the stroboscopic wheel as January 20, 1833.
His first idea was probably inspired by Faraday. H e took u p the subject
of defining the apparent animate movement of objects from the inani-
mate and vice versa, and in 1831 he read a paper before the Royal
Society on “A Peculiar Class of Optical Deceptions, Showing Wheel
Phenomena.” Plateau drew or painted pictures of the movements of
a dancer on the circumference of a circular disk, cut vertical slits in
the cardboard and looked through them at the disk, which revolved
in front of a mirror; a specimen of these cartoons is still extant. 3

About the same time Simon Stampfer, the son of an Austrian day
laborer (1792-1864), independently invented this wheel showing life
in motion. After a most difficult time in finishing his schooling, he
first became professor of mathematics in Salzburg and then served for
twenty years as professor of practical geometry and surveying at the
Polytechnikum at Vienna. 4 He also received his impetus from Fara-
day’s experiments. A detailed statement by Stampfer on this subject
is printed in the eighteenth volume of the Annals of the Polytechnic
Institute. 5 This was a reprint of the pamphlet which accompanied
as explanatory text the second edition of stroboscopic disks sold by
Trentsensky & Vieweg. In the Deutsches Museum at Munich, Stamp-
fer’s original stroboscopic disks are preserved.

Stampfer began his experiments for the production of stroboscopic
disks in 1832, and by February, 1833, had completed six of them. He
applied for an Austrian patent in April, 1833, which was granted
May 7, 1833 (No. 1,920). These disks, with an explanatory descrip-
tion and a preface, were placed on sale in July, 18 3 3. 8 It is worth
noting that Plateau and Stampfer, independently of each other, made
the same invention. The priority right may be questionable, but
Plateau anticipated it by publishing his invention a few weeks earlier.
(For particulars see F. Paul Liesegang, Kinotechnik, 1924, Nos. 19-20.)

EARLY DEVICES FOR MOVING PICTURES 497

That Plateau and Stampfer made the invention independently of
each other was established by PoggendorfF in his Annalen (1834,
XXXII, 646-48). He remarks about the zoescope:

Without doubt Professor Stampfer of Vienna is its inventor. . . . Justly
as his rights are established, there can be no doubt, however, that by a co-
incidence not unknown before in the history of the sciences, he must
divide the honor of the invention with another, namely, M. Plateau of
Brussels. ... At any rate, M. Plateau, in a letter to me in January of this
year, has confirmed the fact that he received the first reliable information
of stroboscopic disks and of their inventor from a casual notice in the
Annalen (XXIX, 189). At his request for more information on these
disks, which after hearing about them from a traveler, he had considered
an imitation of his phantascope, I thereupon sent him a copy of the
pamphlet by Professor Stampfer mentioned above. Considering all this, I
believe, one cannot deny that both Professor Stampfer and M. Plateau are
ro be considered independent inventors of the stroboscopic disks, since
their close contemporaneous ideas and the great distance between Vienna
and Brussels preclude the presumption that either knew or could know
of the other’s invention.

Plateau at first gave no name to his invention; but when in 1833
an inferior imitation appeared in the trade, called phanakitiscope, he
ordered disks made in London from his drawings, which at first were
to be called “phantasmascopes,” but were later named “phantascopes.”
Stampfer also proposed other forms of application for the disks, among
others, their use for serial picture strips. He recognized that at the
moment of viewing the picture should not be subjected to rapid move-
ment.

Plateau’s work in 1828-29 was not concerned with the subject of
the zoescope and did not directly influence its development. Stampfer
would have invented it without Plateau. He was urged by his experi-
ments, however, to study Faraday’s work and to elaborate on it. Only
later, in 1 849, his anorthoscopic experiments changed the form of the
zoescope, because Plateau had applied the anorthoscopic principle.

The first to project serial picture images by means of a Stampfer
“stroboscope” onto a wall and thus produce the illusion of motion
pictures before a large number of onlookers at one time was Franz
von Uchatius. 7 He later became a lieutenant-fieldmarshal and was the
inventor of steel-bronze guns. He was captain of artillery in the cam-
paign of 1848-49 and later taught physics at the Artillery School,
Vienna. He employed the stroboscopic disks in order to demonstrate

498 EARLY DEVICES FOR MOVING PICTURES

to his class various motions, for instance, sound and light waves; it was
necessary to pass the apparatus from hand to hand, since only one
person could use it at one time, which, of course, delayed the lecture.
Therefore Uchatius sought a method which would show various
motions objectively so that they could be seen by all his students at
the same time. He succeeded in this by projecting onto a white wall,
by the aid of a magic lantern, pictures of successive instantaneous
movements which had been painted on a transparent disk. The con-
struction of these pictures was, of course, extremely difficult at that,
time, in the forties of the last century, when photography had not
yet been applied to the taking of serial pictures.

Captain Uchatius presented, on April 4, 1853, to the Vienna
Academy of Sciences ( Berichte , 1853, p. 482) the results of the
experiments which he had begun in 1845 by order of Colonel von
Hauslab, who was the tutor of Archduke Franz Carl’s sons.

Baron Franz von Uchatius was born in 18 1 1 in Lower Austria, the
son of a public road inspector. He volunteered for the army as private
in the Artillery Corps (1829), studied mathematics, mechanics, and
chemistry, attended the Polytechnikum at Vienna, was transferred in
1841 to the gun factory, invented “Uchatius steel” and introduced
(1879) steel-bronze into the Austrian army. He was appointed major
general and knighted. Unfortunately, the experiments to produce
larger calibers out of steel-bronze met with difficulties, and the attempt
to produce a 28 cm. ( 1 1 inch) cannon barrel for coast artillery made
slow progress. These seeming misadventures and a communication
from the War Office that no funds could be made available by the
Reichstag for the production of large-caliber guns so distressed
Uchatius that he shot himself on June 4, 1881 (see Oberst von Ober-
mayer, Geschichte der technischen Milita'r-Akademie, 1904; also
Alfred von Lenz, Uchatius, Vienna, 1904). For us the “apparatus for
the presentation of motion pictures on the wall” is of particular interest;
it was constructed after the principle of the stroboscopic disk and was
published by Uchatius in 1853.

The pictures were, like Stampfer’s, arranged on a circular disk, drawn
freehand, but transparent and stationary. In front of each picture was
a lens which projected it onto the wall as each successive picture image
was illuminated by a light source (Drummond light) , with a condensor
which was turned around the circle by a crank handle. The apparatus
was made and sold by the optician Prokesch in Vienna. 8

EARLY DEVICES FOR MOVING PICTURES 499

The moving pictures so obtained were quite satisfactory and proved
the possibilities of the method. With photographic serial pictures and
instantaneous exposures the method could be perfected. Uchatius was,
without doubt, the first to invent this kind of cinematography with
drawn pictures. His motion pictures attained general approval.

At that time there lived in Vienna a well-known prestidigitator,
Ludwig Dobler (1801-64), w ho dealt with natural magic on a physi-
cal basis and became famous as a juggler, traveling all over Europe as
early as the thirties. He liked to offer surprising physical demonstra-
tions with a projection microscope and a calcium light. He became
also an itinerant lecturer. It was he who, in 1843, brought to Germany
the “dissolving views” which had been shown in England a short time
before. 8

On the occasion of one of Dobler’s performances at Vienna in 1833,
Uchatius spoke to him about his projected moving pictures, which
interested Dobler so much that he went to the barracks where Uchatius
was stationed and, after having seen the apparatus demonstrated, asked
the price. The astonished and modest Uchatius said “one hundred
florins,” whereupon Dobler placed the money on the table, packed up
the apparatus, and loaded it with his own hands into his carriage.

By the purchase of the improved projection zoetrope, constructed
in 1853 by Uchatius, Dobler was enabled ten years after “dissolving
views” were taken to enlarge his program by a splendid number, which
he entitled “Presentation of Living Pictures.” Dobler acquired a large
fortune, bought an estate, to which he retired in his last years and where
he died, 10 while Uchatius, notwithstanding several inventions he made
after this, remained without fortune until his sad end.

General Uchatius must be designated justly as the precursor of
cinematography, because he was the first to project on a wall drawn
stroboscopic pictures giving the illusion of motion. Directly, he has no
share in cinematographic projection, since this is possible only by
means of serial photographs, which were then unknown.

The thought that in order to obtain a good effect the living pictures
should remain stationary for a short time had already been grasped by
Stampfer. The realization of this idea, however, was first attained by
Charles Wheatstone, who back in the fifties installed a cogwheel on
the axle of the disk and ran it by the worm gear. Later (1832), the
optician Duboscq, of Paris, combined the zoescope with the stereo-
scope. The movement of pictures by the action of springs we find

5 oo EARLY DEVICES FOR MOVING PICTURES

realized for the first time in the projection zoetrope of Beale’s “choreu-
toscope” (1866). According to the historical classification of F. Paul
Liesegang, Horner, an Englishman, described in 1833-34 the “marvel
drum.” This well-known form of the zoetrope was later “invented”
over and over again, but only came into general use about 1867. In
1 869 the Scottish physicist Maxwell constructed a “marvel drum” with
an optical adjustment for changing the pictures, by inserting concave
lenses into the viewing slits of the drum. The Frenchman Reynaud
arranged for (1877) a change of pictures by means of a mirror drum
(praxinoscope) which he built in. The first mention of a rapidly chang-
ing exposure interrupted by a rotating shutter, the picture plate being
simultaneously interrupted, is found in American patent No. 92,594,
of August io, 1869, by A. B. Brown. This device corresponds to the
Maltese cross of the modern motion picture apparatus and presents
with it essential characteristics resembling the motion picture ap-
paratus of today.

THE PRAXINOSCOPE OF EMIL REYNAUD

The praxinoscope of Emil Reynaud represents a combination of
the magic latern and the zoetrope. He described it in the periodical
La Nature (Phot. News., 1882, p. 675; Jahrbuch, 1892, p. 363). This
apparatus required only an ordinary lamp. There are two projection
systems, and a single lamp is sufficient for both. One lens projected a
landscape, and so forth, and the other a moving figure. When both
lenses were directed onto the screen and the successive instantaneous
pictures were projected, the figures moved and presented an animated
scene in a somewhat jerky manner. Nevertheless, with such an appara-
tus the correctness of Muybridge’s exposures, which had been ques-
tioned, was practically demonstrated (see Ch. LXVIII) .

He took out a French patent (No. 194,482, December 1, 1888) for
the invention of a perforated flexible picture strip to produce the
illusion of motion. Edison and Lumiere also had perforated strips of
film. Reynaud used his apparatus for the pantomimes at the “Theatre
Optique,” in Paris (1892), and the “Photopeinture Animee” at the
same theater (1896). 11

Emil Reynaud devoted himself in 1877 to the improvement of the
stroboscope, using a rotating mirror drum in order to present princi-
pally the images, optically stationary, to the spectator. He used the
same arrangement later (1889) for projection also. Reynaud’s Erfin-

EADWEARD MUYBRIDGE

501

dung des optischen Bildausgleiches inspired further applications (see
F. Paul Liesegang, Wissenschaftliche Kinematographie, Diisseldorf,
1920) . In Reynaud’s model of 1882 the motion pictures were imperfect
and appeared reversed, notwithstanding the continuing optic compen-
sation, while the series were photographed with intervals too pro-
longed. Later this defect was corrected, and Reynaud made a real
contribution for that period.

Chapter LXVIII. eadweard Muybridge’s

MOTION PICTURE PHOTOGRAPHY

The first serial photographs of human beings or animals in motion
produced by successive exposures at regular intervals were made by the
Englishman Edward James Muggeridge, known as Eadweard Muy-
bridge. 1 He was born at Kingston-on-Thames, April 9, 1830. When
still young, he emigrated to America, obtained a position as clerk, be-
came a professional photographer, and received an appointment from
the United States Government as director of the “Photographic Sur-
vey” of the coast of California. He was engaged in this work on the
Pacific coast in the spring of 1872, when he attracted the attention of
Governor Leland Stanford of California. The governor maintained a
racing stable and had entered into an argument with a gentleman named
Frederick MacCrellish over the question whether or not a horse when
running at full speed at certain moments touches the ground with
only one foot. The Frenchman Dr. Jules Marey had taken up this
question some time before. 2

Dr. Konrad Wolter describes this in detail in Filmtecbnik : 3

A long time before these happenings Jules Marey had considered how
the motions of a horse trotting or galloping could be accurately registered
so that the period during which each foot of the horse touched the
ground could be automatically recorded. In order to accomplish this he
inserted firmly in the hollow of each hoof, which was surrounded by the
horseshoe, a rubber ball from which a long rubber hose led to an inked
pen, which drew a line on a piece of paper stretched around a continu-
ally rotating metal drum whenever the horse put its foot down and there-
by increased the air pressure of the rubber ball. This registering instru-
ment, into which four tubes were inserted and had four corresponding
pens, which were arranged one above the other, was carried in the horse-

EADWEARD MUYBRIDGE

5 02

back rider’s hand. The length of time, as well as the coincidence or the
succession of these strokes, on the registration paper showed the time
lapsed and the reciprocal relation between the lowering and the rise of
each of the four feet of the horse. By the aid of this method, which Marey
called “chronography,” he succeeded, among other things, in demonstrat-
ing that the horse when galloping supports itself first on one foot, then
on three, then on two, and again on one only. Captain Duhousset, who
was not only a fine horseman and lover of horses but also a clever artist,
was so fascinated with these experiments, that he made drawings for
Marey from the chronographs he had made showing the respective posi-
tions of the horse in motion.

These drawings by Duhousset, which had their origin in Marey’s
chronographs, were reproduced, and copies came into the possession of
Governor Leland Stanford, of California, an enthusiastic friend of horses
and owner of a racing stable. Governor Stanford believed these drawings
to be very questionable.. He was particularly skeptical of the drawing
which depicted the galloping horse touching the ground with only one
forefoot. Stanford believed this to be impossible; he discussed the matter
with his friend MacCrellish, and out of the discussion came the happy
idea, so momentous for the future, to settle the matter in dispute by the
aid of photography, an idea at once strange and novel, considering con-
temporary photographic technique. Marey had never thought of such a
possibility up to that time. Stanford gave Muybridge an order for the
carrying out of this experiment, which, as we know, led Muybridge to
devote his whole life to the perfecting of serial photography in the an-
alysis of movement. This had another consequence: Stanford entered into
direct communication with Marey in Paris and informed him also of his
experiment. This called Marcy’s attention to the possibilities which pho-
tography offered, which he exploited later with such skill and ingenuity
in his chronophotography. Marey, of course, communicated with Muy-
bridge, who kept him informed on the progress of his work and the
splendid success which attended his work in America in the production
of serial photography of fast-moving objects. In due time Marey received
from Stanford and from Muybridge, full confirmation of the correctness
of his own chronographic equestrian pictures. Muybridge’s photographs
made at Palo Alto, California, at Stanford’s request in 1872 furnished the
proof of the drawings made from Marey’s serial chronographs.

Muybridge ordered a horse to be ridden on a race track at Palo Alto,
alongside of which he set up from twelve to thirty cameras side by side,
but spaced slightly apart. The track was covered with rubber matting,
and strings were stretched across the ground which led to the instan-
taneous shutter of the cameras, which functioned automatically.

EADWEARD MUYBRIDGE

5 ° 3

When he began his first experiments, Muybridge had only wet col-
lodion plates at his disposal and obtained only weak outlines of the
horse passing in front of the camera.

In May, 1872, he constructed instantaneous shutters for short ex-
posures and made his first experimental negatives at the race course
in Sacramento, Cal. The imperfect pictures were sufficiently sharp
to show the silhouette of the trotting horse; some, indeed, indicated
that the trotter undoubtedly raised all four feet simultaneously from
the ground. Marey’s drawings were examined and found correct.

The first photographs, however, lacked continuity and showed
only accidental, isolated positions of the trotter. Muybridge conceived
the idea of obtaining a connected record of all phases of the motion of
the horse in exactly regulated time spaces. He interested Governor
Stanford in this idea, so that he put at his disposal the thoroughbreds
at his racing stables at Palo Alto, Cal. This location is now occupied by
the buildings of the Leland Stanford University. There Muybridge
set up his battery of twenty-four cameras in a row parallel to a white
wall. At first he tried to obtain the exposures automatically by me-
chanical means of stretching across the track wires which led to the
lens shutters. Later he operated the shutters at exactly determined time
intervals, by means of an electrical device, which functioned auto-
matically. This arrangement was described in the Proceedings of the
Royal Institution of Great Britain, March 13, 1882.

Instantaneous photographs of the racing horse “Sallie Gardner.”
which ran at the rate of 52 y 2 feet per second and was photographed at
successive intervals of 1/25 of a second are reproduced in the 1932
German edition of this History (p. 296). In the original, however, the
contours are not so sharp as in the reduced illustration.

In 1878 Muybridge published a pamphlet under the title The Horse
in Motion, which he copyrighted. In a second publication (a quarto
of 203 pages) appear numerous illustrations depicting athletes, horses,
dogs, and other animals in motion. The Scientific American Supple-
ment (1879, No. 158, p. 2509) printed several similar pictures.

The obvious idea occurred to Muybridge to stretch his long strips
of photographically produced serial motion pictures in the long-known
American “wonder drum.” He also tried to frame stereoscopic serial
pictures in two of these drums, which were fixedly combined with
each other and, with a simple mirror device (after the manner of
Wheatstone’s reflex stereoscope), gave the illusion of a seemingly cor-
poreal small trotting horse in action.

EADWEARD MUYBRIDGE

5°4

In 1879 Muybridge invented the zoopraxiscope. It consisted of a
revolving tin disk, in which were inserted one or more concentric
rows of glass diapositives in a certain order; they passed through a pro-
jection apparatus. The disks carried a collection of as many as two
hundred single views. These serial pictures Muybridge exhibited with
his projection-stroboscope before large audiences.

Muybridge gave the first performance with his zoopraxiscope in
Palo Alto, in 1879, and in 1880 he gave one before a large circle of
persons in San Francisco. In the middle of 1881 Muybridge went to
Europe with his serial-diapositives and the zoopraxiscope. He gave his
first lecture in September, 1881, in the laboratory of the physiologist
Professor E. J. Marey, who was very enthusiastic over this new in-
vention and was incited by it to employ photography also in his simi-
lar investigations, which led him later to his “chronophotography.”
From Paris Muybridge went to London (March, 1882), and there, as at
Paris, he achieved extraordinary success. Up to now his work had been
done with wet collodion plates. This period ended in 1879. Later he
took his work up again, using gelatine silver bromide plates, when Dr.
William Pepper, president of the University of Pennsylvania, Phila-
delphia, urged him to continue his investigations there on a broader
basis. With this most encouraging support he began, in the spring of
1884, his most fruitful activities, which ended in the fall of 1885 as
far as photographic exposures were concerned. During these one and
one-half years he used more than one hundred thousand Cramer dry
plates. The time intervals of a series were always measured by a chrono-
graph and graphically recorded. 4

The material gathered from his photographic exposures was pub-
lished in 1887 under the title Animal Locomotion: an Electro-photo-
graphic Investigation of Consecutive Phases of Animal Movements ,
University of Pennsylvania, 1872-85 (London, Eadweard Muybridge,
1 o Henriette Street, Covent Garden, c. 1887). The large edition of this
work embraces eleven volumes, with 781 large mezzotint gravure in-
serts, illustrating more than 20,000 single successive phases of loco-
motion (price 1 10 guineas) , while the small edition, with selected illus-
trations, cost 20 guineas. 6 The book contains serial pictures of human
beings and animals (horses, donkeys, steers, dogs, cats, lions, elephants,
camels, birds and so forth) .

Muybridge found it unexpectedly difficult to sell enough of these
expensive books to justify their publication and came, in 1891, even

EADWEARD MUYBRIDGE

5°5

to Austria in order to find subscribers. He also visited the author and
presented him with some of the illustrations. He also gave numerous
lectures in Germany in 1891-92 and sold a number of copies of his
works to German libraries.

The invention of the above-mentioned zoopraxiscope by Muy-
bridge was of the greatest importance. To him belongs the priority
right for the invention of the zoetrope projection with glass diaposi-
tives and counterslotted disks, which dates from 1879. Muybridge him-
self, in March, 1882, projected his pictures before the Royal Society
in London by the use of such an apparatus illuminated by electric
lights. In 1891 he exhibited these pictures also in Vienna and Berlin.

The great progress which these pictures showed astonished all who
saw them. That they had defects did not remain undiscovered, but
these notwithstanding, Muybridge’s projected serial photographs were
a pioneer’s work. Muybridge was well aware of the importance of his
invention, for he remarked about his zoopraxiscope that it was “the
first instrument which was ever constructed or invented to show by
synthetic reconstruction motions which had been photographed from
life.” Therefore Muybridge must be recognized as the real inventor
of the first projected animated photograph from life.

In 1893 he had his own exposition building at the Chicago World’s
Fair, which he called “Zoopraxographical Hall.” On this occasion he
published two textbooks: E. Muybridge, Descriptive Zoopraxography;
or, The Science of Animal Locomotion, University of Pennsylvania,
1893, and E. Muybridge, Popular Zoopraxograph ; the Science of Zoo-
praxography, published at the Zoopraxographical Hall of the World’s
Columbian Exposition, 1893.

With this the successful life work of Muybridge was completed;
he never went beyond the use of glass negatives and diapositives, nor
did he ever turn to the production of serial photographs on films or
paper. In 1900 he returned to his birthplace in England and retired
from business. He died on May 8, 1904, and bequeathed his zoopraxi-
scope to the public library of his native town. Leland Stanford, Jr.,
University, at Palo Alto, California, honored him in 1929 by erecting
a bronze tablet to his memory.

Chapter LXIX. PHOTOGRAPHIC ANALYSIS

OF MOVEMENT BY JANSSEN AND MAREY

The french astronomer Professor Pierre Jules Cesar Janssen 1 ( 1 824-
1907) employed photography in 1874 to obtain a chronographic
photo-record of the positions of the planet Venus during its transit
across the face of the sun. He invented a special “photographic re-
volver” for this purpose, with which forty-eight instantaneous ex-
posures in juxtaposition were taken around the edge of a circular,
rotating light-sensitive plate in rapid succession . 2 A series of photo-
graphs of Venus during its passage in front of the sun at intervals of
seventy seconds, photographed by Janssen, is reproduced in Marey’s
Developpement de la methode graphique (Paris, 1884).

The photographic apparatus of Janssen was based on the principle
that the sensitive plate moved forward at certain intervals, but re-
mained stationary during the exposure. He employed in this the Mal-
tese cross, which later played an important role in motion picture
photography. Janssen had an excellent astronomical observatory at
Meudon, where he lived until his death; his lectures were delivered
in Paris.

The palace in Meudon, used by the Empress Marie Louise and later
by Prince Napoleon as a summer residence, was destroyed in the
Franco-Prussian War of 1870-71. Restored by the Republic, it was
equipped as an observatory for Janssen. On a visit of this author in the
spring of 1889, on the occasion of the International Conference for the
Production of Photographic Celestial Maps, 3 he found that Janssen
had produced the granulation of the sun’s surface in very large size
on wet collodion plates. Janssen also demonstrated the absorption
spectrum of water in very long tubes in calcium light. In 1880 Janssen
had obtained in the strongest sunlight (with refractors) , while work-
ing with gelatine silver bromide plates, as well as on collodion-tannin-
dry-plates, a repetition of the solarization phenomena. The different
phases through which the picture passes are: (1) a negative; (2) neu-
tral condition (total intensification); (3) a positive; (4) a second neu-
tral condition, in which the plate becomes uniformly light in the de-
veloper; ( 5) a negative of the second order; (6) a third neutral condi-
tion of uniform intensification (Janssen, Cortrpt. rend., June, 1880,
XC, 1447, and XCI, 199). He also worked on the laws of density in
normal negatives.

JANSSEN AND MAREY 507

JULES MAREY

The French physician Etienne Jules Marey (1830-1904), professor
at the College of France, devoted himself particularly to the physi-
ology of motion of men and animals and the scientific possibilities of
motion pictures. After the work of Janssen and Muybridge became
known, he analysed the phenomena of motion in men and animals by
photographic methods, for which he constructed his own chrono-
graphic apparatus. He invented a series of registering appliances to
serve as exact aids independent of the individuality of the observer,
for the analysis of very complicated and fleeting physiological func-
tions; for instance, the heart action, with the aid of the sphygmograph,
the gait of horses and dogs, the flight of birds, and so forth.

Marey employed for his motion studies apparatus with movable
photographic plates and also stationary plates on which the instan-
taneous pictures appeared next to each other on a single plate. His
apparatus equipped with movable plates followed closely the earlier
photographic revolver and followed exactly Janssen’s astrophoto-
graphic telescope.

Marey’s photographic gun for taking serial pictures of birds in flight
was equipped with a sight and a clock movement; it permitted twelve
exposures in a second, each exposure occupying 1/720 of a second of
time of exposure on Monckhoven’s gelatine silver bromide plate.
Photographs of a gull in flight are reproduced in the Handbuch (1893,
1(2), 582-84). Marey mounted the serial pictures thus obtained on a
stroboscopic disk, where, notwithstanding their small size, the phe-
nomena of motion could be observed.

Jules Marey 4 was assistant surgeon in a Paris hospital in 1855, then
he took up the science of human and animal physiology and the ani-
mated motion of the body. He became professor of medicine at the
University of Paris; in 1872, a member of the Academy of Medicine;
and in 1876, a member of the Academy of Sciences. He founded the
Institute for Physiology (Institut Marey) at Paris. In all his researches
after 1882 Marey employed the systematic methods of serial photog-
raphy.

He invented, in 1 888, the “chronophotograph” from which later was
developed the modern cinematograph. Marey was for many years
president of the Societe Frangaise de Photographic and took a lively
interest in the arrangement of the photographic division of the Paris

5 o8 JANSSEN AND MAREY

Exposition of 1900. His scientific friends and admirers presented to
him (1902) an artistic plaque which shows his portrait and a symbolic
design of the different apparatus and the results of his investigations. 5

Marey’s chronograph with stationary plates was installed in a mov-
able roomy darkroom (wagon) . It consisted of a large rotating disk
of 4 14 feet diameter with a slot opening on the circumference. The
slot measured a one-hundredth part of the periphery of the disk, so
that when the disk turned ten times in a second, each exposure took
one-thousandth of a second.

Marey had his actors clothe themselves in white and had them pass
in front of a black background; he used only one camera and one lens.
The speed of the rotating disk was controlled by a round dial with a
shining movable hand which was fastened on a dark background. For
special motion studies Marey clothed the actors in black and fastened
bright metal bands on their hands, legs, and so forth, in order to indicate
more plainly the movements in the photographs. In another series of
experiments the clothes worn were half white and half black, so that,
for instance, when walking, only one side of the body was visible.

Later, Marey greatly improved his apparatus (Marey, La Photo-
graphic du mouvement, Paris, 1892). After 1890 he used a new serial
apparatus, the photochronograph, in which was used a strip of negative
paper, moved by a spring which was 3 / 2 inches wide and not more
than 157V2 inches long. The strip was not perforated, winding iself
continuously from spool to spool and remaining stationary for a mo-
ment during the exposure. The instantaneous shutter consisted of two
slotted disks, rotating closely behind each other, one of which turned
five times as fast as the other; when two of the slits cut in the periphery
coincided, the exposure took place.

These photographs were not suitable for projection, owing to the
unequal distances between pictures (“steps”) . There were also lacking
at that time a transparent film suitable for projection. About the same
time Marey invented an instrument for making serial micro-photo-
graphs and subsequently also high-frequency-current serial negatives,
with electric arc lamps, at the rate of 120 pictures a second. Thus, in
1 890 Marey photographed with his chronograph not only persons in
motion but also jellyfish, fish, insects, and the movements of blood
corpuscles in the capillary vessels.

In 1893 George Demeny, in Paris, who assisted Marey in his experi-
ments, built an apparatus arranged for taking and projecting serial

JANSSEN AND MAREY 509

photographs with a beater (“ Schlager ”) carrier inserted; this beater
was, much later, frequently employed in cinema projection. This inven-
tion lay unemployed until exploited in 1 896 by Gaumont (at first with a
film 2 y 6 inches wide) after Edison and Lumiere had made their “cine-
matoscope” public.

Many admirers and friends of Marey regarded him as the real in-
venter of modern cinematography, while generally the brothers A.
and L. Lumiere were recognized as its creators. A movement in protest
against the designation of the brothers Lumiere as the inventors of
cinematography developed in France, proceeding mostly from Marey’s
pupils, which we report below because the document describes Marey’s
services comprehensively. 6

Protest against the Serious Injustice Committed against the Eminent
French Physiologist E. J. Marey, by Those Who Desire to Contest His
Right to the Invention of the Cinematographic Process and of Having
Constructed the First Cinematograph.

All we former pupils of E. J. Marey consider it our imperative duty
solemnly and energetically to express our firm conviction that the cinema-
tographic process and the first cinematograph are the work of Marey and
represent the crowning result of his labors, extending over almost half a
century. The automatic and true-to-nature delineation of motion in all
its forms, particularly of all animated phases of life, was the task to which
he devoted himself without cessation.

From 1858 to 1882 the simple graphic method or chronostylography,
after the description of his friend and collaborator Chauveau, formed the
essential tools in his work.

Thus came into existence successively the sphygmograph, the cardio-
graph, the myograph, the several registering devices with movable plates
or rotating cylinders, the odograph, the chronograph, etc., all of which
are apparatus of classical importance, which have been described in sci-
entific literature and have become indispensable elements of the equip-
ment of every biological research laboratory.

In the pursuit of this object, clearly tending toward one definite goal,
Marey, since 1882, was convinced that chronostylographs did not suffice
to disclose the several phases of the complex manifestations which are
presented by the motions of men and animals, the flight of birds and
insects.

From this period on he sought a new method, and thus photography
became his favorite pursuit, to which he devoted until the end of his life
his scientific activities and his remarkable gift for invention.

It was he who created animated photography, or cinematography.

5 io JANSSEN AND MAREY

Since Marey’s death (1904) the brothers Lumiere have asserted that
they are the inventors.

A simple comparison between the work of Marey and that of the Lu-
miere brothers, by means of the development of the facts and their chron-
ological succession, suffices to show in relief and in a striking manner
Marey’s priority rights.

Marey’s Work on the Animated Picture

1882: Marey invents a chronophotographic apparatus with stationary
plates and chronographic disk shutter, which produced in equal time in-
tervals pictures of successive phases of motion of objects on black back-
ground (Compt. rend., August 7, 1882, Vol. XCV).

1882 and subsequently: Marey endeavors to eliminate the necessity of
the black background and constructs the photographic gun, an apparatus
with movable plates and rotating mirror.

1888: Marey substitutes in place of the stationary plate of his chron-
ograph of 1882 a strip of light-sensitive paper and drops the regular inter-
mittent movement in the picture plane of the lens. The paper strip re-
mains stationary during the time of the opening of the disk shutter
(Compt. rend., October 15 and 29, 1888, Vol. CVII). Here the basic
principle is for the first time expressed and materialized which forms the
real foundation of cinematography.

1889: The International Photographic Congress adopts Marey’s recom-
mendation of the term “chronophotography” for describing the several
methods which serve to obtain the photography of motion.

Marey induces Balagny, of Paris, to introduce strips of emulsion coated
celluloid, which advantageously displaced the light-sensitive paper of
1888.

1890: Marey describes, in a report to the Academy of Sciences, his
new apparatus equipped with a transparent light-sensitive film. This is the
first cinematograph for taking animated pictures.

1892: Marey constructs, according to the reversible principle of the
chronophotograph, an apparatus for the projection on a screen of series
of pictures taken by the afore-mentioned apparatus and thus realizes the
photographic synthesis of motion (Compt. rend., May 2, 1892).

1893: Marey becomes conscious of the fact that his process promises
to have far-reaching application and decides to apply for a patent (June
29, 1893). Unfortunately, the principle of animated photography on flex-
ible, transparent film suitable for rapid intermittent movement had be-
come public knowledge since his report of 1890, and the law denies all
rights to industrial and economic ownership of an invention which has
been made public before application for a patent. An unjust and unfair
law! The industrial and financial advantage can accrue, therefore, to the

JANSSEN AND MAREY 511

originator of a single improvement, which is all he needs to patent in or-
der to reap the result of the original invention, in which he had no part.

1894: Marey publishes his book Le Mouvement, which collected his
earlier work and contains the history of the invention of cinematography.

The Work of Messrs. Lumiere on the Animated Picture

1895: A. and L. Lumiere patent an “apparatus for the taking and pro-
jection of chronophotographic pictures” (February 13, 1895).

They open a showroom in Paris, December 28.

Marey’s work shows clearly the thread leading to cinematography, an
invention which since 1892 is perfected and final in its basic elements.
Messrs. Lumiere have evidently done nothing more than add a technical
improvement to this basic invention.

In place of the name given to it by Marey, which was adopted by Lu-
miere, “chronophotography,” the term “cinematography,” introduced by
Leon Bouly, has been accepted and brought into general use. But this is
only a change of names. Marey is and remains, for the impartial expert,
the creator of animated photography and of the chronophotographic anal-
ysis and synthesis of motion on a flexible transparent film, in a word, of
cinematography.

The protest is signed by:

R. Anthony (professor at the Museum of Natural History); J. Athan-
asiu (professor in the University of Bucharest; formerly subdirector of
the Institute Marey); L. Bull (subdirector of the Institute Marey); L.
Camus (member of the Academy of Medicine, director of the Institute
Superieur de Vaccine); F. Cellerier (director of the Research Laboratory
at the Conservatoire Nationale des Arts et Metiers); G. Contremoulins
(chief of the Main Laboratory for Radiography at the Hospitals); A. Do-
leris (member of the Academy of Medicine); E. Gley (professor of the
College de France, vice-president of the Academy of Medicine); L. Hal-
lion (member of the Academy of Medicine); L. Manouvrier (professor at
L’Ecole d’Anthropologie); R. Marage (professor at the Sorbonne); M.
Mendelssohn (ex-professor University of St. Petersburg, member of the
Academy of Medicine); P. Nogues (laboratory director of the Institute
Marey); Dr. Felix Regnault; Ch. Richet (member of the Institute, pro-
fessor on the Faculty of Medicine, director of Institute Marey); G. Weiss
(dean of medical faculty, Strassburg, member of Academy of Medicine,
former subdirector of the Institute Marey).

For comparison we print below an article from Science, technique,
et industries photographiques, May, 1926 (p. 55), which refers to the
foregoing protest and shows how divided opinions are, even in France.
The article reads:

OTTOMAR ANSCHUTZ

5 12

It was inevitable that the dedication of the Lumiere commemorative tablet
would arouse again a new clamor among the people who are more Ma-
rey’istic than Marey himself and have made it their affair to twist the
facts, without submitting to a discussion. In the Paris Soir, March 24, we
leam that the Lumieres have robbed Demeny or something of the sort.
This is a new version. Formerly the followers of Marey, of which any-
how some have patented and exploited their inventions in this field, could
find no words harsh enough to censure Demeny’s action, who construct-
ed an apparatus for chronophotographic exposures (but without projec-
tion) and had the temerity to turn it to his own account instead of yield-
ing the paternity to his master. At present there is being disseminated a
polemic of Dr. Richet, who seems to have forgotten that he himself had
admitted, in a letter to the late E. Wallon, the correctness of the record
taken during the course of a discussion in which he participated, in which
he was clearly determined that there was no foundation whatever for the
campaign against the brothers Lumiere, which was carried on under his
leadership.

For further information see Chapter LXXI and following.

Chapter LXX. OTTOMAR ANSCHUTZ RE-
CORDS MOVEMENT BY INSTANTANEOUS PHOTOG-
RAPHY AND INVENTS THE ELECTROTACHYSCOPE
(1887)

Great merit for the progress of serial photography, as well as for that
of instantaneous exposures in general, must be accorded to O. An-
schutz, of Lissa and later of Berlin ( Handbuch , 1892,1 (2), 592).

Ottomar Anschutz (1846-1907) was a professional photographer
in Polish Lissa. 1 He perfected instantaneous photography by the intro-
duction of the focal-plane shutter (although it was not invented by
him), which was attached immediately in front of the photographic
plate. Anschutz made, in 1882, single instantaneous exposures and at-
tracted attention in 1884 with his instantaneous exposures of pigeons
and storks in flight, which possessed sharpness and considerable
size, which had not been attained before that time. 2 His photographs
furnished exceedingly valuable material for the study of animal life
and the mechanics of flying. One of these original photographs, which

OTTOMAR ANSCHUTZ

513

pioneered the further improvement of instantaneous photography,
is reproduced in the 1932 German edition of this History (p. 718).

From 1885 Anschutz devoted himself to the pictorial presentation
of animals and human beings in motion by continuous series of ex-
posures. On orders from the Prussian government, horses in different
gaits (24 exposures in % second) were photographed; the original
photographs were very small ( % x 1 1 / 2 inches) and were later enlarged.
Anschutz was far more successful and more precise in obtaining the
optical synthesis of these serial photographs into “moving pictures”
than all his predecessors. He also used transparencies, which, how-
ever, he did not project on a wall, but which could be “looked through”
by a large number of people simultaneously. In the first form of the
“electric rapid viewer,” which Anschutz invented in 1887 and exhibit-
ed in Berlin and Vienna, the serial pictures (glass diapositives) were
arranged in a circle on a steel disk. 3 At the lightest point was an opal
glass, behind which the illumination of the field of the picture took
place with the aid of an instantaneous flashing Geissler tube in corre-
sponding intervals of time.

The original form of the “electric rapid viewer of Anschutz was
exhibited on the invitation of the author in 1887 at the Vienna Graph-
ische Lehr- und Versuchsanstalt. This was the first apparatus which
presented, in a perfect manner to a small circle of onlookers, animated
photographs, employing photographic serial pictures (glass diaposi-
tives) . This presentation excited great attention at the time.

This kind of electric illuminating device was retained also in the
later form of Anschutz’s electrotachyscope (1890), while the form of
the stroboscope was changed; in place of the rotating disk, a rotating
drum (a kind of wheel) was used, which made the apparatus easier
to handle and less bulky and also permitted the showing of various
pictures next to one another, while with the disk form only one series
could be observed, and then the diapositive had to be changed ( Hand -
buck, 1893, 1 (2), 396).

The electrotachyscope consisted of a rapidly moving drum to which
were attached a number of transparent gelatine silver bromide prints
(on flexible paper). The light source (Geissler tube) was installed be-
hind the diapositive, and a ground glass inserted between the light and
the diapositive softened the flashlight of the Geissler tube through
which the electric current flowed.

This kind of stroboscopic “rapid viewing ” 4 is of only historic inter-

DEVELOPMENT OF CINEMATOGRAPHY

est. Modern cinematography turned to flexible strips of transparent
film, both for the taking of the negative as well as for the projection
of the positive picture.

Chapter LXXI. DEVELOPMENT OF CINEMA-
TOGRAPHY

Cinematography had its beginning in stroboscopic vision and the sub-
sequent connection with moving pictures, which we have described
before.

A comprehensive description of the history of the art of projection
and cinematography is presented by F. Paul Liesegang in the Liesegang-
Mitteilungen, October, 1928. The history of the development of cine-
matography is depicted in a diagram which shows that the cinemato-
graph (1895) evolved from the combination of three inventions, the
magic lantern ( 1 660) , the stroboscope, or “wheel of life” (1832), and
photography (1839).

HISTORY OF THE PERIOD PRECEDING MODERN CINEMATOGRAPHY

Ducos du Hauron had already conceived the principle of the idea
f or the construction of cinema apparatus in 1 8 64, but he did not execute
it. His invention was not made public, and he cannot, therefore, be ac-
corded any part in the realization of this idea.

Ducos du Hauron patented in France, March 1, 1864, his apparatus
(No. 61,976) for taking moving pictures with optical equalization
under the title “Apparatus Having for Its Purpose the Photographic
Reproduction of Any Kind of a Scene, with All the Changes to Which
It Is Subjected during a Specified Time.” He also took out a supple-
mentary patent, December 3, 1864. The apparatus was never con-
structed, the description of the patent was never published, and his
directions remained unknown at that time. In his supplementary patent
application he substituted a light-sensitive strip for the rigid photo-
graphic plates. For the projection of the picture an artificial light with
a condenser was used. Ducos du Hauron’s idea was far ahead of his time.
The battery of stationary lenses and the passing shutter proposed by
him was put into practice by Humbert de Molard in 1867, and the
arrangement of rotating lenses described in the additional patent was

DEVELOPMENT OF CINEMATOGRAPHY

5i5

realized thirty years later by the American Jenkins, who had no knowl-
edge of the earlier work of Ducos du Hauron . 1

A strong impulse came from Marey, who by 1888 had already con-
structed his apparatus for the production of serial photographs with
negative paper strips and was therefore repeatedly called the “founder
of modern cinematography. 2 But Marey’s apparatus lacked character-
istic elements of the modern cinema apparatus; he used no transparant
films, no perforation of the film strips, which render the single ex-
posures equidistant, no intermittent forward movement, but an elec-
tromagnetic arresting adjustment, and no sufficiently large size of
picture (3V2 x 3V2 inches). Marey therefore cannot be recognized as
the inventor of modern cinematography. 3

CINEMA CAMERAS WITH STRIPS OF FILMS OF FRIESE-GREENE
(1889) AND SIMILAR APPARATUS

Friese-Greene 4 and the engineer Mortimer Evans invented, in 1 889,
a camera for making rapidly successive series of photographs on a long
unperforated strip of celluloid film, which they patented on June 21,
1889. The film remained stationary during the time of exposure and
was moved only afterward. The movement was effected by a handle
turned by hand, which also caused the instantaneous shutter to func-
tion. The film strip contained enough material for three hundred
pictures, ten every second.

Friese-Greene first demonstrated this camera in 1890 before the
Photographic Society at Bath; and in July of the same year, at the
Photographic Convention at Chester. At this time he had also con-
structed a projection apparatus for it.

Friese-Greene was led to his invention by J. A. Roebuck Rudge of
Bath in 1882. The latter worked at that time on the production of
serial photographs on a glass disk, naming the apparatus “bio-phanta-
scope.” After Rudge’s death Friese-Greene continued the experiments,
at first with glass plates and intermittent exposures, whereby the serial
pictures were rolled off spirally (1885). In 1889 he started the use of
celluloid films, and on June 21, 1889, he took out, jointly with Evans,
who had assisted him in building his cinema camera and his projection
apparatus, a patent for cinema celluloid films. The city of Bath erected
in 1927a memorial tablet to Rudge and Greene. Edison had founded the
Motion Picture Trust of America against Greene and others, but
Greene’s patent remained valid. At any rate, Edison is considered

5 i6 development of cinematography

the first to introduce the perforated motion picture film on a practical
scale. In August, 1889, W. Donisthorpe and W. C. Croft took out
an English patent on an arrangement quite the same as that of Greene
(No. 19,912), and L. Breeman was granted a similar patent with
paper bands on February 18, 1890. Demeny patented, on September
1, 1892, a “photoscope,” and on December 19, 1893, on a process of
chronophotography. Demeny accomplished the electrical connection
by the “punch,” which later occupied a prominent position, but was
then displaced by the Maltese cross.

£The following paragraph was sent to the translator by the author.]

C. Francis Jenkins played a noteworthy role in the introduction of
motion picture photography in America. He constructed, in 1893,
a motion picture projection apparatus called a “phantascope” and a
“phantascope camera,” for which a U. S. patent was granted, January
12, 1894. The intermittent motion was accomplished by perforated
films. The machine was first exhibited to the public at the Atlanta
Exposition, October, 1894; the projector had no intermittent shutter.
This apparatus is exhibited at the National Museum in Washington.
Jenkins was the founder of the Society of Motion Picture Engineers
of America. Although he made no particularly important inventions,
his activity in America was so highly regarded that he was awarded
the Gold Medal by the Franklin Institute in 1925.

Louis Aime le Prince (1842-1890), a Frenchman who lived most
of his time in either England or America, must be included among
the precursors of motion pictures. He studied in France and also in
Leipzig, went to Leeds (England) in 18 66, took out on November 2,
1877, an American patent, No. 376,247, and on January 10, 1888, an
English patent on motion pictures and their projection. In 1888 he
produced twenty serial pictures per second with a one-lens-perforated-
film camera and projected his pictures at Leeds. An English Com-
mittee convinced of his priority rights, erected a memorial tablet to
him at Leeds, 1931 (Phot. Jour., May, 1930; Kinotechnik, 1931, p. 224).
Le Prince arranged a motion picture presentation on March 3, 1890,
at the Paris Opera House. When traveling in France, at the time at
which he was to prove the functioning of his apparatus to the French
Patent Office, he disappeared, leaving no trace behind him (1890),

£The remainder of this section was sent to the translator by the
author.]

William Friese-Greene (1855-1921) learned photography in his

DEVELOPMENT OF CINEMATOGRAPHY

early years and was employed in 1882 by J. A. RudgeinBath, England,
who at that time was occupied with the production of serial photo-
graphs on glass plates on which the serial images were rolled spirally
under intermittent exposures. This apparatus Rudge called “bio-
phantascope.” After Rudge’s death Friese-Greene continued these
experiments and demonstrated his apparatus in 1885 and 1887 before
the Photographic Society of Great Britain. He established, in 1888,
a photographic business, which he neglected, however, and produced
motion pictures on photographic paper strips. They were impregnated
with oil and thus made semitransparent. In January, 1888, he used
perforated paper rolls for both the taking and the projecting camera.
In 1888 he substituted film rolls for paper, which caused him a great
deal of difficulty, for he succeeded in producing some strips of emul-
sionated films. The films were perforated only on the corners and
were propelled by rollers. The mechanism of his apparatus Friese-
Greene constructed, together with his friend Mortimer Evans, and
they took out a patent on June 1, 1889, which subsequently became of
great importance.

According to this patent the film was not in motion during the ex-
posure, and only then resumed its motion. The motion was accom-
plished by a crank, moved by hand between the rollers, which also
caused the instantaneous shutter to function. The cameras produced
300 pictures at about 10 per second.

The first scene was filmed in October, 1889, by Friese-Greene in
Hyde Park Corner, and it was projected at the Photographic Conven-
tion in the Town Hall in Chester in 1 890 ( Scientific American Supple-
ment, April 19, 1890, No. 746). In a later camera, constructed by the
mechanic Lege, made for Greene at the end of 1889, the films were
already perforated on both sides (Will Day, Phot. Jour., 1926, p. 359).

Friese-Greene devoted himself also with great skill to the field of
stereoscopic motion picture and color photography. We learn from
the British Journal of Photography (1921, p. 281) that Friese-Greene
possessed an extraordinary talent for inventions and a superior skill
for mechanics, although he never rose above an elementary concep-
tion of chemistry and physics. Fortunate though he was in his inven-
tions, he died in straightened circumstances, having expended all his
means on an invention for printing without inks by electricity and
on other inventions. A memorial tablet was erected to Rudge and
Greene in 1927 at Bath.

5 i8 DEVELOPMENT OF CINEMATOGRAPHY

Edison and Friese-Greene started a patent suit. Edison had founded
the Motion Picture Trust of America in order to combat those parts
of Greene’s patents which interfered with his own. Friese-Greene suc-
ceeded in having Edison’s claim for a patent rejected by the United
States Supreme Court, which declared Friese-Greene’s patent the
master patent of the world in cinematography.

Notwithstanding this, Edison is considered the first to introduce the
perforated motion picture film into practice.

edison’s kinetograph and kinetoscope (1891)

The many-sided inventor Thomas Alva Edison (1847-1931), con-
ceived the idea in 1 889 of taking serial photographs and had a camera
for this purpose, which he called the “kinetograph,” constructed by
the Eastman Kodak Co. in Rochester in that year. Eastman also fur-
nished the film. The apparatus for viewing the pictures Edison called
the “kinetoscope.” 5

In July, 1891, the daily papers carried the news of this most in-
genious invention made by Edison. Accompanied by an extended
advertising campaign, Edison described his invention, claiming that
he would present animated scenes through serial pictures and that he
would also reproduce musical performances, speeches, and so forth
through a combination with the phonograph. 6

The kinetoscope was offered for sale in 1893. It was an apparatus
for viewing pictures, with a continuous moving strip, 35 mm. (1 %
inch), which in construction was not superior to the early stroboscope.
But of the greatest importance was the use of perforated celluloid
film strips for serial exposures, of which the measurements were later
generally adopted. R. W. Paul constructed such kinetoscopes in Eng-
land in 1 894.

Edison’s patent of 1891, which was not published until 1897, re-
ferred to a camera for taking the pictures and to a perforated strip of
film. Edison later claimed the sole right for the use of perforated
motion picture films. The patent suit, however, led in 191 2 to a denial
of Edison’s claim.

In 1893 the Edison Company exhibited serial photographs through
their viewing apparatus in many places. Edison was the first to intro-
duce the very small picture sizes (still in use today) and made with an
attached electric motor 46 exposures a second, also in half a minute
about 1,400 small pictures on a perforated strip of film 49 % feet long.

DEVELOPMENT OF CINEMATOGRAPHY

519

For the presentation a sort of peep box was used (kinetoscope) , which
had an eyepiece attached on top. After the money was deposited in a
slot, a lamp lit up, and the motion mechanism presented the pictures
in a life-like manner. The apparatus made its appearance in the spring
of 1895 at a show called “Venice in Vienna” in the Prater, and in
Berlin somewhat later. 7

Edison’s photographic studio was very simple and unattractive. An
illustration in Die Pbantasiemachine, by Rene Fiillop-Miller (c. 1931),
shows the first of Edison’s film studios, which at that time (the end of
the 19th century) was called “the Black Maria.” As a counterpart of
this primitive studio of the early times, a picture of the modern thirty-
story skyscraper, which houses the offices of the Paramount Pictures
Corp. and the Paramount Theater, is shown by Fullop-Miller.

The American Le Roy saw one of these kinetoscope exhibitions in
December, 1893, which induced him to construct a projection ap-
paratus. With such an apparatus, invented by him, and with Edison’s
kinetoscope films, which were then on sale, Le Roy exhibited on June
6, 1894, in the store of an optician named Riley, in New York, pro-
jected motion pictures to an audience consisting of theatrical agents.
It is maintained by Americans that this was the first objective motion
picture projection (E. Lehmann, “Zur Geschichte der Kinemato-
graphie,” in Kinotecbnik, 1931, XIII, 223-28).

Edison later projected his serial photographs with his own apparatus,
but all these preliminary experiments and inventions were excelled
by the cinematograph of the brothers A. and L. Lumiere at Lyon; they
must be considered the creators of modern cinematography. The
Lumieres also used from the start the word “cinematographe,” although
this term had been used by others for other apparatus. 8

THE BROTHERS LUMIERE INVENT, IN I 895, THE MODERN CINEMATOGRAPH

The brothers Auguste and Louis Lumiere, owners of a large dry-
plate factory at Lyon, constructed and offered for sale under the
name “cinematographe” their remarkably simple and efficient appara-
tus for taking and reproducing serial pictures, in which for the first
time the perforated film strip was held and moved by a gripper (French
pat., February 1 3, 1895; German pat., April 1 1, 1895) . 9 The first appa-
ratus was constructed by Carpentier in Paris. Lumiere’s “cinemato-
graphe” had an overwhelming success, and from this dates the modern
advance of motion picture technique.

DEVELOPMENT OF CINEMATOGRAPHY

5 2 °

The first presentation of Lumiere’s cinematograph took place on
December 28, 1895, on the ground floor of the Grand Hotel, Paris.
A memorial tablet affixed to this house was dedicated on March 17,
1926, and reads: “Here on December 28, 1895, took place the first
public projection of animated photography by the aid of the cinemato-
graph apparatus invented by the brothers Lumiere.”

The enormous spread of the motion picture, with its far-reaching
economic consequences, brings along with it France’s claim that this
invention was originated by Frenchmen. This was agitated by the
“Chambre Syndicale des Directeurs de Cinema,” the Municipality of
Paris, and the Commission for Old-Paris. The detailed report is given
in Bull. Soc. franp. phot. (August, 1921, ser. 3, VIII, 225-49). The
discussion was reopened in October, 1925, as to whether the brothers
Lumiere or Marey was to be considered the real inventor of cinematog-
raphy. This brought about a meeting of the Photographic Society of
Paris, at which the members approved of the text inserted on the tablet,
but the wish was expressed that a memorial tablet be also affixed to
Marey’s workshop at 1 1 Boulevard Delessert, Paris (Bull. Soc. ftanp.
phot., 1929, ser. 3, XVI, 33, 137). The society added that Marey de-
served the fullest appreciation as inventor of chronophotography, but
that cinematography was actually bom on the day when long series
of animated photographs were presented for the first time to a large
audience. These conditions were fulfilled first, with great success, on
December 28, 1895, by Messrs. A. and L. Lumiere, with the aid of the
apparatus invented and named by them “cinematographe.”

The Lumieres had started the manufacture of celluloid film for
motion pictures in 1887 and had bought the celluloid from the Celluloid
Company of New York. Later, Eastman began the manufacture of
motion picture film at Rochester and developed such a large industry
that his company today supplies the greatest part of the world con-
sumption of motion picture film. He had also supplied Edison with
films for his “kino” apparatus from the start. The largest European
film factory was erected by the company for anilin manufacture (I. G.
Farbenindustrie A. G.) in Berlin; this has been moved to Wolfen (Kr.
Bitterfeld). The C. P. Goerz factory in Dresden, Zeiss-Ikon, must
also be mentioned. Louis Lumiere was elected a member of the French
Academy of Sciences in 1920.

In 1 896 Lumiere-Casler brought out the “kinora,” which produced
a continuous serial picture when the prints, on paper, were moved

DEVELOPMENT OF CINEMATOGRAPHY

5 2 1

rapidly from the lower unbound edge of the pack; they soon stopped
producing them.

The firm Lumiere, at Lyon, shortly afterward put on the market
their kino projection apparatus with a small number of positive films.
They were equipped with gelatine silver bromide diapositives on
celluloid strips about 4V4 feet long and 0.1375 inches thick.

The life work of the brothers Lumiere is covered in an interesting
survey in the Bull. Soc. frang. phot. (1921, p. 225). Their work in
photochemistry and research, their accomplishments in the technical
industry, in the field of color photography, in cinematography, and
more, is described and substantiated by numerous citations giving the
original sources.

Lumiere’s cinema apparatus was presented at London on December
28, 1895. In the German countries it was first introduced at Vienna on
March 20, 1896. Then it appeared at Berlin, and soon it had spread
all over the world. At the World Exposition at Paris, 1900, the brothers
Lumiere projected their motion pictures on large wall surfaces and
proved their capability for mass production. These pictures, of which
the author saw a presentation at that time, were perfect in every way.
They also showed the first educational films for medical men and sur-
geons; in one of them they represented the amputation of a leg by a
celebrated surgeon— in all its gruesome details.

The first presentation of the Lumiere cinematograph at Vienna
demonstrated the beginning of this new technique, which makes the
following detailed description of historic interest.

At the beginning of 1896 Lumiere sent a projection apparatus and
camera to the author in Vienna, who demonstrated the astonishing
results at the Graphische Lehr- und Versuchsanstalt before an invited
audience, who were delighted with them. The cinema apparatus con-
sisted of a small wooden box, in which the film roll was drawn inter-
mittently in front of the lens of an electric projection apparatus by
the aid of wheels, rolls, and by turning a handle, the film falling into
a basket; the fire hazard was entirely neglected. The condenser of the
electric light consisted of a glass ball (Bohemian glass) filled with water,
in which hung a piece of charcoal to eliminate the disturbing air
bubbles.

The films used at that time were at the most fifty feet long and the
performance lasted about one minute. The whole program at these
first presentations comprised no more than nine of these picture series,

DEVELOPMENT OF CINEMATOGRAPHY

5 ^

namely, a gateway of the Lumiere factory at Lyon, a carnival at Nice,
the arrival of a railroad train and of a steamship, the beach of a seashore
resort, children at play, and so forth.

Shortly after the appearance of the Lumiere “cinematographe,”
Gaumont-Demeny, in Paris, Pathe, and others constructed similar
apparatus.

Motion picture films were manufactured in France by Pathe-Cinema
at Vincennes (Seine) among other manufacturers; they later became
the Kodak-Pathe Soc. Anon. Frang., Paris.

The establishment Gaumont introduced various types of cinemat-
ographs, such as small cinema apparatus and amateur cinematoscopes.
Gaumont also showed, in November, 1902, after Decaut’s specifica-
tions, a synchronized phono-cinematograph at Paris. In England R.
W. Paul constructed the first commercial cinematograph in March,
1896, and presented it at the Alhambra, London.

At the turn of the nineteenth century many applied themselves to
the improvement of motion picture apparatus. The first to show pro-
jected film pictures in Germany was Max Skladanowsky in 1 895. 10
The American Jenkins, who had constructed a compensating camera
with rotating lenses in 1894, provided in 1895 a gear single-tooth cog-
wheel, with a cross consisting of many parts, for moving the film.
The multipartite Maltese cross appeared first in November, 1 896, in
a French patent of Bunzli and Continsouza. It was later introduced
by Robert Paul in London (“theatrograph”) and by Oskar Messter,
in Berlin, who used before this a seven-part and a five-part cross,
respectively. The American Casler, the inventor of the “mutoscope”
(1894), a viewing apparatus with a picture cylinder, introduced in
1 896 in his “biograph” the “cam change,” which has meanwhile died
out (F. Paul Liesegang).

About 1900, laws were passed (presumably first in England) for
the management of motion picture theaters and for fire prevention,
due to a horrible conflagration in a Paris theater which cost many
human lives.

Later, priority claims sprang up for the invention of motion picture
apparatus and their first presentation. We mention here the work of
the Viennese photo-technician Theodor Reich.

According to the statement of Professor Karl Albert, 11 backed by
letters and documents, Reich had already, in May, 1895 (a half year
before Lumiere), produced in London the first perfect films and had

DEVELOPMENT OF CINEMATOGRAPHY

5 2 3

projected them in private circles, but nothing had been published
about them. He did not apply for an English patent until June, 1896,
which was granted on June 3, 1896 (No. 1228) under the title “Im-
provements in apparatus for making or exhibiting zoetropic and similar
pictures.” Since the English Patent Office does not examine, when a
patent application is received, whether the invention is novel or not,
and since the publication of Reich’s patent did not take place until
after that of Lumiere, the latter’s priority can hardly be contested.

The history of the subject is exhaustively dealt with by G. M.
Coissac in his Histoire du cinematograpbe (Paris, 1925).

TIME LAPSE AND SLOW MOTION PICTURES

For the history of time-lapse photographs it must be mentioned that
the Austrian physicist Professor Ernst Mach, in Prague, was the first
to express, in 1888, the thought ( Jabrbuch , 1888, p. 286) that through
the accelerated stroboscopic reproduction of very slow serial exposures,
lasting for days or months, previously unknown laws of metamorphoses
might be discovered; for instance, in the growth of plants , 12 in the
development of an embryo, or in the laws of nature, and so forth. He
also mentioned how instructive it would be if the course of the planets
could be reduced as to space and time, ideas which were realized (Zeiss’s
Planetarium) only much later by those who had no knowledge of
Mach’s earlier work. Much later, not until 1896, Georges Gueroult
attracted attention when he caused to be opened a letter deposited on
June 11, 1889, with the Paris Academy of Sciences, which contained
the same idea of time-lapse.

The “slow motion” represents the opposite procedure and is used
for the analysis of motion. Several thousand motion pictures are taken
in a second and then projected at the normal speed of sixteen per
second.

The frequency is limited in the case of intermittent film changing
with special claw construction. Up to 250 pictures a second have been
attained. With higher frequencies it is necessary to use optical com-
pensation for the movement of the image. A practical compensating
arrangement using mirrors was invented by August Musger (1869-
1929). Musger was born in Styria, was educated for the priesthood,
and became also a professor of drawing and mathematics. He con-
structed mirror cinema-apparatus, received a German patent on it in
1905, exhibited his apparatus in 1907 before the University of Graz

5 2 4 PROJECTILES AND AIR EDDIES

(Styria), and thus became the founder of an entirely new construc-
tion of film apparatus. The exploitation of Musger’s world patents
was to be carried out by a company in Ulm (Germany), but they met
with financial reverses, and the patents expired. Musger applied later
for various new patents. Dr. H. Lehmann, a film technician in Dresden,
took up Musger’s patent, coined the name “Zeitlupe” (slow motion)
for this apparatus, and the firm of Ememann, in Dresden, marketed it.
The rights to the invention Lehmann gave to Musger unreservedly.
Musger was never financially successful, but worked with self-denial
as teacher and inventor (a biography by Albrecht Graf von Meran
is in Filmtechnik , 1929, p. 503).

SMALL FILMS

The normal size of motion picture films was standardized by Edison
as 35 millimeters (negative size 18 X 24 mm.) . After many experiments
the Eastman Kodak Company brought out, in 1923, small films of
16 mm. and Pathe (Paris) put out films of 9.5 mm. widths (H. Pander,
Filmtechnik, 1931, No. 15). •

Chapter LXXII. PHOTOGRAPHING PROJEC-
TILES IN FLIGHT AND AIR EDDIES

The first attempts to enlist photography in the service of military
technique dates back to the middle of the last century. The tests were
carried on especially at the arsenal at Woolwich, by Marey at Paris
and by Ottomar Anschutz in Germany. For ballistic purposes it was
sought to obtain pictures of the projectile in its flight. Sunlight and
automatic instantaneous shutters with complicated arrangements were
adopted for this purpose. The results were useful to some extent.

As early as 1866 a cannon ball in flight was photographed by the
ordinary method of instantaneous photography at the Woolwich
arsenal in England.

Perfect pictures, however, were attained only after 1884, when
Professor E. Mach, in Prague, introduced the electric spark as the
light source.

This ingenious method Ernst Mach 1 first worked out in 1884 and
completed in his Physical Institute at Prague in the years 1 8 8 5 to 1887.
He caused the projectile shot from a pistol or a gun to cut through

PROJECTILES AND AIR EDDIES

wires enclosed in glass tubes; this released a strong electric spark which
furnished the illumination for the compressed air wave ahead of the
projectile, the whirl of the air behind it, and the cloudy appearance
in the firing line (Geitel, Max, Siegeslauf der Technik, Stuttgart, 1910,
III, 655). Especially important is Mach’s original report in Jahrbuch
( 1 888, p. 287).

Ernst Mach, physicist and philosopher (1838-1916), was professor
of physics at the University of Graz (Styria), then in Prague, and
from 1895 to 1901 professor of philosophy at the University of Vienna.
In his work on physics he often referred to photography, and he
worked out the first apparatus for the measurement of sensitivity by
means of rotating sector wheels. He also devoted himself with re-
markable success to the study of the flight of projectiles and the re-
sulting air eddies by means of instantaneous photography.

On these experiments Professor Anton Lampa writes in the Vienna
Neue Freie Presse, July 28, 1926:

Of Mach’s physical experiments the best known are probably his studies
of flying projectiles. They have recorded his name in the history of bal-
listics, a science in which he had no fundamental interest. It was not his
intention to serve ballistics as a military science, which enlisted his co-
operation, but the purely technical interest of the scientist whose atten-
tion had been drawn accidentally to a phenomenon in the ballistic field.
Mach himself relates that in 1881 he attended a lecture in Paris by the
Belgian expert in ballistics, Melsen, who expressed the opinion that pro-
jectiles at a high velocity push ahead of them a volume of compressed
air; he believed that he thus could explain certain explosive effects of

penetrating projectiles. Melsen’s explications aroused in Mach the desire
to investigate this conception by experiments, because the experimental
method was in principle ready at hand.

It was brought to the highest perfection by Professor August Toepler,
1 865, in his method of investigating air eddies, which can be traced back

to Huygens. This is based on the natural phenomenon which we may ob-
serve occasionally in bright sunshine out-of-doors, in the air eddies which
are generated in the surrounding cooler air by the warm air rising from
hot surfaces; it is a fact that air of different densities presents different
properties of light refraction (see Mach’s popular lecture on his experi-
ments, given November 10, 1897, before the Vienna Society for the Dis-
semination of Knowledge in the Natural Sciences under the title “Er-
scheinungen an fliegenden Projektilen”; also the 4th ed. of Mach’s popu-
lar scientific lectures published in Leipzig, 1910).

The first experiment was made in 1884 with a target pistol. The missile

526 PROJECTILES AND AIR EDDIES

itself started the illuminating spark when it reached the middle of the
field of vision of the photographic apparatus. The picture of the missile
was obtained without difficulty; very delicate pictures of sound waves,
generated by the illuminating spark, appeared on the dry plates, but the
air compression which it was hoped to record did not show. Mach
searched at once and in the right direction for the explanation of the
failure. He determined the velocity of his missile and found it to be 240
mm. (787.4 feet) per second; therefore, considerably less than the ve-
locity of the sound. He quickly recognized that under these circum-
stances no appreciable compression could take place, since it advances
with the velocity of the sound (340 mm./sec.; 1,115 f eet P er second) and
thus is in advance of the projectile and escapes.

He was so firmly convinced of the existence of air eddies (formed by
air compression in advance of flying projectiles), at a velocity of the pro-
jectile greater than 1,115 f eet P er second, that he requested Professor Dr.
Salcher, of the Naval Academy in Fiume (Austria), to carry out the ex-
periment with a projectile of correspondingly high velocity. Salcher
made such tests in the summer of 1886, exactly according to Mach’s direc-
tions, and the expected result was at once obtained. The result coincided
exactly in its form with the sketch which Mach had previously drawn.
Further tests by Salcher with a cannon and Mach’s own trial with a big
gun supplied by Krupp furnished additional progress which, however,
confirmed Mach’s conviction that “really good results are only obtainable
by the most careful execution of the tests in a laboratory suitably
equipped for this purpose.” He therefore continued his experiments in
his laboratory (Physical Institute of the German University of Prague),
which was possible, because the size of the projectile was of no conse-
quence, since small ones show the same phenomena as large ones. He was
assisted by his son Ludwig in this work, and the most successful experi-
ments were later executed by Ludwig alone. The phenomena surrounding
the projectile flying at a velocity in excess of that of sound resemble the
phenomena in the water surrounding a ship proceeding at high speed.

Professor Lucien Bull, Marey’s successor in Paris, applied Mach’s
principle of illumination by an electric spark in such a way that he suc-
ceeded in obtaining oscillating spark discharges (2,000 discharges per
second) and thus exposures at the speed of 2,000 in one second. He
photographed with this, among other subjects, the movement of the
wings of insects.

Still higher velocities were reached by Professor C. Cranz, in Berlin
(1909), with a ballistic cinematograph. As light source he used a
high-frequency machine with alternating current. He improved the

5 2 7

PROJECTILES AND AIR EDDIES

process for ballistic military purposes in Germany. Some years later
Cranz’s method was introduced into the Austrian army.

In Mach’s process only a single exposure of the projectile was
possible. Professor C. Cranz, of Berlin, succeeded in 1909 in con-
structing a ballistic cinematograph ( Zeitschr . fur das Gesamte Schiess-
und Sprengstoffavesen, 1909, IV, 17), which enabled him by an ex-
posure which lasted one-tenth of a second, to take 500 photographs,
which followed each other in a time interval of one five-thousaftdth
of a second.

About 1909 Dr. Cranz began his work on the photographic method
of measurement of the velocity of infantry projectiles and tested the
use of a direct-current spark discharge interval for motion pictures
of ballistic and physical phenomena, and so forth, which is reported
in Jahrbuch (1910, pp. 159, 232; 191 1, p. 533). Cranz was able to take
a great number of pictures per second with his apparatus and pro-
duced photographs of projectiles in flight and of the effect of shots.
These pictures were exhibited publicly at the International Photo-
graphic Exhibition in Dresden in 1909. He also made serial pictures
of air eddies with the aid of electrical sparks. Later, Cranz became
director of the Institute for Technical Physics at the Technical College,
Berlin. He presented a survey of his sound and ballistic photographs
at Dresden, 1931.

Paul Schrott also used cinematography of air eddies for further
studies ( Kinotechnik , 1930, p. 40).

In Austria, Major Franz Duda devoted himself to the construction
of apparatus for serial photographs of cannon projectiles in flight in
daylight, in order to determine the course of the flight. Owing to
his scientific knowledge, he was attached to the technical adminis-
trative military committee, where he made his investigations. The
author was fortunate to see splendid proofs of such serial photographs
in 1913. The World War saw Duda an officer of heavy field artil-
lery in Serbia and Galicia; he was recalled to Vienna during the war
and worked on all the proving grounds with his measurement ap-
paratus.

He had built three serial apparatus for the serial photography men-
tioned. The last one and the most perfect was no longer of any use
in the new Austria, and Duda, who had to pay for the mechanical
work out of his own pocket, was compelled to sell his apparatus abroad
in order to pay the accumulated bills. We hear that his ideas have

ARTIFICIAL LIGHT IN PHOTOGRAPHY

528

been taken up in Germany, England, and America. Chronic throat
trouble necessitated an operation from which he died in 1928.

Chapter LXXIII. artificial light in pho-
tography

The physicist Seebeck observed in 1812 that Bengal fire emits strong
actinic light and that it explodes detonating chlorine gas. The first
photographic reproduction obtained on daguerreotype plates by the
light of an ordinary oil lamp was probably made by the brothers
Natterer, 1841.

“Oxyhydrogen calcium light,” which is produced by heating a lime
cylinder under an oxygen blast to white heat, which then gives a
glaring white light, was known long before the time of the daguerreo-
type under the name “Drummond lime light.” Thomas Drummond
is called the inventor of calcium light in most literary sources ( 1 8 2 6 ) , 1
which, however, is erroneous. This question of priority was agitated
during Drummond’s lifetime, and it is due to Drummond’s fairness
that we are able to produce a written, authentic statement of the case.
It was Sir Galsworthy Guerney (1793-1875) who discovered the
calcium light, which was named after Drummond because he used it
first in public, in 1826-27, f° r his trigonometric work in Ireland.
Drummond himself admitted that he had no claim to the invention.
The inventor, who demonstrated his light before the Earl of Sussex
and the Earl of Kendal (later King Leopold of Belgium) was then
honored with a medal ( Jahrbuch , 1902).

The strong chemical action of the electric arc light on chlorine
detonating gas was recognized by Brandes ( Annales de cbimie et de
physique, Vol. XIX). It seems that Silliman and Goode were the first
to use the arc light for daguerreotypes. In November, 1840, they
photographed a medal by an electric arc light of 90 Daniell elements.
Berres had also used it in 1840 for microphotography.

Fizeau and Foucault demonstrated, in 1844, that the chemical illumi-
nating power of the Drummond calcium light was less than that of
an electric arc light of forty galvanic elements. They compared the
luminosity of calcium light, electric light, and sunlight, optically and
photographically, on daguerreotype plates, and were the first to find
that the chemical and optical luminosities of the light source were

ARTIFICIAL LIGHT IN PHOTOGRAPHY

5 2 9

not proportionate to each other {Annul, de cbim. et de phys., ser. 3,
XI, 3 70). This was also determined later by Bunsen and Roscoe (1859)
in their studies on the action of illuminating gas and carbon monoxide
flames on chlorine detonating gas.

Drummond’s calcium light and Talbotype paper were used by David
Octavius Hill experimentally for his portraits in 1841. He used blue
muslin to soften the harsh light and exposed for one-half minute
( Daguerrean Jour., 1851, I, 217). This experiment was, however,
never repeated. Calcium light was later used only for enlarging and
projection, and eventually it went out of use, being displaced by the
electric arc light.

The electric carbon arc light could be produced at first only with
galvanic batteries. In November, 1840, Silliman and Goode 2 used it
in making daguerreotypes; they employed the electric arc from 90
Daniell elements. By this light they made with a single lens a daguerreo-
type of a medallion in twenty seconds. Similar experiments were made
by De Monfort, 1846, also by Gaudin, 1853.

The practical application of an electric arc lamp for photograph-
ing people seems to have been inaugurated by Aubree, Millet, and
Leborgne in 1851 ( Compt . rend., XXXIII, 501); they used fifty Bunsen
galvanic elements. Lucenay devoted himself, in 1852, to this kind of
portrait photography.

Gaudin and Delamarre patented, in France, in 1854, without regard
to the priority claims of their predecessors, the use of electric arc lights
and of Bengal light in portrait photography. They applied a novel
illuminating device by bringing the light into the focus of a parabolic
silver-plated copper mirror. The eyes of the sitter were protected from
the glare of the illuminating source by inserting a small spherical mirror
in front of the arc light, which reflected the light back into the parabolic
mirror. In addition there was a blue glass inserted before the arc, and
the studio skylight was covered with blue paper.

Nadar, in 1861 and 1862, photographed, with great difficulty the
famous underground catacombs in Paris by the light of a galvanic
arc light. The results aroused great excitement at that time.

At the December 21, 1863, session of the Paris Photographic Society,
Nadar exhibited portraits taken by electric light. He exposed his wet
collodion plates 60 to 85 seconds, using a white-painted reflector.

Adolf Ost, in Vienna, also used electric light in taking portraits
and exhibited satisfactory pictures on May 17, 1864, at the Vienna

ARTIFICIAL LIGHT IN PHOTOGRAPHY

530

Photographic Society (Phot. Korr., 1864, p. 11). He used two big
batteries, one of which, with 80 Bunsen elements, furnished the prin-
cipal light, while the smaller one, of 40 elements, served to illuminate
the shadows. Blue-glass globes were employed to soften the glaring
light.

In 1866 Saxon & Co., Manchester, used old-style electromagnetic
generators of Wilde, London, for the carbon arc light in making en-
largements (T albotypes ) , and were proud when they produced twenty
life-size photographs in one evening (Phot. Archiv, 1866, p. 385; and
1867, p. 338).

But not until the introduction of the dynamo was the general utili-
zation of the electric arc light made possible. Van der Weyde 3 intro-
duced “photography at night” (1876-78) and carried on a regular
portrait studio by electric light at the Paris Exposition of 1878; then
A. Liebert, in Paris, followed. He established, in 1 879, a night studio,
using electric light generated by a Gramme dynamo, and made photo-
graphs of full figures by the aid of large white reflectors.

Later, in 1903, Liebert perfected his technique by surrounding a
a large arc lamp with a reflector shade, to which he added a circle of
electric bulbs. This produced a softer and more harmonious illumina-
tion, while permitting short exposures. Electric lighting in photog-
raphy found later extensive application in the reproduction processes,
in printing negatives and enlarging them. 4 The details of these various
processes for photography by artificial light are reported in the Hand-
buch (1892, Vol. I, Part 2 and 1912, Vol. I, Part 3).

Magnesium light began to compete with the electric light. Bunsen
and Roscoe, at Heidelberg, pointed out, in 1859, the considerable
chemical action of burning magnesium. Almost at the same time
William Crookes, in London, made the same observation and im-
mediately tried to employ magnesium light in photography. About
1864 magnesium was used in large measure in photography, because
in the meantime it became available on the market in larger quantities.

Magnesium light was successfully used in photography by Brothers,
at Manchester (1864). He photographed Faraday in the presence of
the audience after a lecture at the Royal Institution. In Berlin (July,
1864) the first successful trials were made about the same time by
H. W. Vogel in the presence of Carl Suck, Remele, and Poggendorff.
Vogel took a portrait of I. C. Poggendorff on wet collodion plates,
exposing fifty-five seconds.

ARTIFICIAL LIGHT IN PHOTOGRAPHY

53i

The Royal Astronomer o f Scotland and director of the Edinburgh
Observatory, C. Piazzi Smyth (1819-1900), made interesting photo-
graphs of the interior of the Great Pyramid (Egypt) with burning
magnesium wire in 1865; Brothers also did this in mines in 1864 (Phot.
Archiv, 1865, p. 330). As early as 1864 Sonstadt, in London, used
magnesium light in the course of his portrait photography (Phot.
Archiv, 1864, p. 209). The Magnesium Company, Boston, recom-
mended in 1865 the use of smoke bags for catching the fumes emitted
by the burning magnesium wire. The bags were kept from collapsing by
crinoline hoops (Phot. Arch., 1896, p. 340). Magnesium lampsequipped
with wires on spools wound off by hand originated with W. Mather, of
Salford, and F. W. Hart, of Kingland. Alonzo Grant, in America,
was probably the first to use a clock movement to wind the wire (Phot.
Arch., 1865, p. 377). On the Perkins magnesium lamp see Phot. Korr.
(1889, p. 229) ; this lamp furnished the basis for the Bohm lamp, which
came later.

Nadar, who was the first to photograph the Paris catacombs with
electric light, later used magnesium light, owing to its simplicity, in
photographing subterranean canal construction. The amateur photog-
rapher Leth, of Vienna, photographed the sarcophagus of Empress
Maria Theresa in the imperial burial vault about 1865, and Fr. von
Reisinger, professor at the Polytechnikum in Lemberg (Galicia), in
1867 photographed reliefs on stone and sarcophagi in the Lemberg
catacombs also by magnesium light.

The interior of the stalactite cave at Adelsberg (Austria) was photo-
graphed on wet collodion plates by Em. Mariot, of Graz (Styria) , in
1868, by the light of a burning magnesium strip. These prints have
become very rare; they are reproduced in the 1932 German edition
of this History (p. 743 ) .

The first directions for preparing rapidly burning fuse compounds
with magnesium powder, which was later called flashlight powder,
originated with Traill Taylor in 1865® (mixture of magnesuim powder
and potassium chlorate, sulphur, and antimony sulphide). These ex-
periments led, however, to no practical results in photographic por-
traiture and so forth, because of the slight sensitivity of the wet collo-
dion process, then generally used, and on account of the high price of
magnesium powder. Traill Taylor’s experiments were therefore soon
forgotten. Equally unsuccessful was the attempt of Larkin to bum
magnesium powder in lamps (1866).

ARTIFICIAL LIGHT IN PHOTOGRAPHY

53 2

G. A. Kenyon, in 1883, followed with experiments employing mix-
tures of magnesium powder with pure potassium chlorate and observed
the powerful photographic effect produced by burning magnesium
wire in an atmosphere of oxygen. He also made portraits by such a
light, and noticed at the time that mixtures of magnesium powder and
potassium chlorate could be used to produce a brilliant light. The re-
sultant smoke prevented him from further pursuit of this observation
(Brit. Jour. Phot., 1883, p. 61).

Photography with magnesium powders in the form of “flashlight,”
as it is called, was notably advanced by the work of J. Gaedicke and A.
Miethe, at Berlin ( 1 887),® and soon came into general use everywhere,
because the explosive mixtures recommended by them for these mag-
nesium powders (magnesium, potassium chlorate, antimony, sulphide,
and later other mixtures) as a fact burn as fast as a flash and make in-
stantaneous pictures of persons, groups, and so forth, possible on gela-
tine silver bromide plates.

The use of Gaedicke-Miethe’s magnesium flashlight powder, which
contained an explosive mixture of potassium chlorate and antimony
sulphide, was discontinued later, owing to the danger of explosion. It
was displaced by the so-called “harmless” flashlight mixtures of mag-
nesium with manganese peroxide, strontium and thorium nitrate (Agfa
flashlight), etc. This is reported in detail in Handbuch (1912, Vol. I,
Part 3).

Bunsen and Roscoe, in Heidelberg, determined in 1859 the high
actinism of magnesium light; Schrotter of Vienna recognized the rich-
ness of magnesium light in ultraviolet radiation. The spectra of mag-
nesium light and of the various flashlight mixtures were given by Eder
and Valenta, Atlas ty pise her Spektren (Vienna, 1928). A spectral
comparison of Drummond’s calcium light with sunlight by the author
(Denkschriften der Wiener Akad. d. Wissenschaft, 1892) was pub-
lished in Eder and Valenta’s Beitrdge zur Photochemie und Spektral-
analyse ( 1 904) .

Photometric investigations on the chemical luminosity of burning
magnesium, aluminum, and phosphorus were published by the author
in the Sitzungsberichte of the Vienna Academy, 1903 ( Handbuch ,
1912, Vol. I, Part 3). He also determined the color temperature of the
various light sources used in photography.

In the eighties of the last century the superior properties of pure
magnesium powder, burned in a flame, became known, which furnished

ARTIFICIAL LIGHT IN PHOTOGRAPHY

533

ample illumination for instantaneous photographs on gelatine silver
bromide plates. Shortly after the publicizing of Gaedicke-Miethe’s
flashlight powder, T. N. Armstrong pointed out that pure magnesium
powder blown through a flame gives an intensive light (Brit. Jour.
Phot., 1887, p. 77). A large number of different magnesium flashlight
lamps were manufactured after these directions, which are described,
together with experiments with aluminum flashlight, in another vol-
ume of the Handbuch.

The flashlight candles for interior photography were anticipated by
the slow-burning fireworks. 7 They were introduced into modern
photographic practice by York Schwartz, of Hanover (1887), (Ap-
ollo, December, 1887). There were many varieties of magnesium
flashlight (Handbuch, 1912, Vol. I, Part 3).

Photography by gas light was made practical only by the introduc-
tion of orthochromatic plates. The use of Auer’s incandescent light
advanced photography temporarily.

Incandescent gas light was invented by Carl Auer von Welsbach in
1885 and improved by the introduction of thorium. The use of ligroin
gas with compressed air instead of illuminating gas for Auer’s incandes-
cent mantles in photographic enlarging and printing was invented by
the mechanic Fabricius, in Vienna (1889).

Mercury light with an electric arc was known as early as the sixties
(Handbuch, 1912, Vol. I, Part 3). The first practical mercury-vapor
lamp was constructed by Leon Arons, of Berlin, in 189 2. 8 These
mercury lamps were perfected in 1901 by the American Cooper-
Hewitt (1860-1921). By the use of special glass (ultraviolet pre-
viously) the “uviolglass-mercury lamp” of Schott (Jena) came into
existence. This was followed by the mercury quartz lamp of Heraeus
(Hanau), in 1903.

The mercury light and the improved arc light have recently been
partially displaced by the modern gas-filled, metal-wire incandescent
lamps, which, in combination with highly color-sensitive plates, have
been increasingly used for photography of all kinds. The greatest de-
velopment in the technique of artificial illumination in photography
is found in the motion picture studios.

Chapter LXXIV. printing-out processes

WITH SILVER SALTS

The printing-out process with paper made light-sensitive with sil-
ver salts reaches back in its first beginnings to Hellot, 1737, Scheele,
1777, and Wedgwood and Davy, 1802. Talbot described silver chlo-
ride paper for photographic printing, which he prepared by first “salt-
ing” the paper with a common salt and sensitizing with a silver nitrate
solution. He was the first to carry out, following Herschel’s direction,
the fixation of prints with sodium thiosulphate. Talbot also found that
silver bromide paper was suitable for the printing-out process (1839),
but silver chloride paper persisted, because it gave a stronger black
color.

Talbot and Herschel therefore laid the foundation for our modern
photographic printing-out process on silver chloride paper. To these
two Englishmen belongs the merit of having made possible photo-
graphic printing on paper and of having found the best medium for
fixing, namely, hypo.

Talbot also recognized the great importance of these photographic
printing processes for those purposes which we call, in short, “photo-
graphic tracing.” He not only produced in 1839 prints of drawings
but also sent, on March 23, 1840, to the French Academy of Sciences
facsimile photographic copies of old manuscripts and documents made
in printing frames. Their accuracy and legibility met with the highest
approval of the members of the Academic des Belles-Lettres. 1

Daguerre recommended a method for the preparation of silver
chloride paper. Biot reported this method, which Daguerre supposedly
had known since 1826, to the French Academy of Sciences on Eebruary
18, 1 8 39- 2 He saturated paper with “hydrochloric acid ether,” then
with silver nitrate. The prints were imperfectly fixed by washing in
water. Daguerre’s method was, however, not accepted in photographic
practice.

Since the history of printing on silver paper is given in detail in
Handbuch (1928, Vol. IV, Part 1), the author confines himself here to
the most important points.

Taylor reported in 1840 that an improved paper for photographic
printing could be obtained if paper salted with common salt was im-
pregnated with ammonio-nitrate of silver; 3 Talbot described in 1844
a similar preparation. 4 In modern times (1903) Valenta used am-
moniacal silver in the silver chloride collodion emulsion for celloidin

PRINTING-OUT PROCESSES

535

paper and found that this was especially suitable for celloidin-mat
paper for platinum toning. 5

To Blanquart-Evrard we are indebted for the coating of paper with
substances which overcome the roughness and porosity of the paper
surface and thus produce a greater fineness in silver prints. He devoted
himself to Niepce’s negative process, published in 1847, with albumen
or starch coating on glass and found in 1850 that albumen and milk
serum act favorably on negative paper development as well as on posi-
tive-printing-out paper. Blanquart-Evrard presented his method with
albumen paper for positive prints to the French Academy of Sciences,
May 27, 1850 ( Compt . rend,., 1850, XXX, 663), and described the
preparation of positive paper with albumen, which he salted with
sodium chloride and sensitized with a concentrated silver solution
( 1 : 4 } •"

Thus the methods for preparing positive paper with albumen, starch,
and gelatine were known in the early fifties; attention was also already
directed to the addition of organic acids in the preparation of silver
print paper. In 1856 T. F. Hardwich investigated more closely the
behavior of silver citrate in the positive printing process (Jour. Phot.
Soc., London, 1857, III, 6; Kreutzer, Jahresbericht f. Phot., 1856,
p. 2 3 ) . He prepared paper with a mixture of sodium citrate, ammonium
chloride, and gelatine, and sensitized it in a bath of silver nitrate solu-
tion. Hardwich found that the silver citrate which formed in sensitiz-
ing with silver influenced the image favorably.

The use of starch paste added in the salting of the printing paper
was introduced by De Brebisson (Horn’s Phot. Jour., 1854, II, 6 and
47). He coated paper with a boiled tapioca starch, to which he added
chlorides.

All these photographic printing processes were later practically ap-
plied. At first the starch-filled silver chloride paper was preferred,
then, in the sixties, first the single- and later the twice-albumenized
paper. The gelatine papers, as well as those prepared with chloro-
citrate, were then abandoned.

Adolf Ost, of Vienna, invented in 1869 the permanent silver print
paper which was produced by addition of a great deal of citric acid
to the silver bath.

After the silver print papers (especially albumen papers) which are
sensitized in a bath had maintained their leadership for twenty-five
to thirty years, they met with strong competition because of the intro-

536 PRINTING-OUT PROCESSES

duction of permanent emulsion print papers. The strongest impulse
was given by the work (1864-65) of G. Wharton Simpson, who elab-
orated the collodio-chloride silver emulsion printing process, later
called “celloidin process.” Of great importance were the experiments
(1867 and 1868) of J. B. Obernetter, of Munich, who was the first to
manufacture collodion paper on a large scale. Adolf Ost introduced
a collodio-chloride paper which permitted the picture image to be
transferred to other supports.

The Bavarian photochemist J. B. Obernetter (1840-87), who ap-
plied his inventive genius to numerous branches of photographic re-
production technique, 7 was not only the first to manufacture collodio-
chloride papers on a commercial scale but also the first to use it in
printing large editions for the illustration of German photographic
technical journals. He called attention to the sharpness of definition
in the prints and proved that collodio-chloride prints surpassed albumen
prints in permanency. Nevertheless, professional photographers used
albumen prints until about 1890 for all kinds of portrait and landscape
subjects and accepted the yellowing of the prints as a necessary evil.

The widespread popularity of amateur photography following the
introduction of gelatine silver bromide dry plates urged the necessity
for permanent and easily workable printing papers. About 1 890 gela-
tino-chloride silver emulsion papers (“aristo” papers) and collodion
silver chloride papers (“celloidin” papers) captured the market to
such an extent that the consumption of these papers soon surpassed
that of the earlier albumen and starch papers. It was Abney who
brought about the manufacture of modern gelatine chloro-citrate print-
ing papers, in 1882. 8 Emil Obernetter, of Munich, son of J. B. Ober-
netter, manufactured gelatino-chloride paper on a large scale from
1884 and thereby laid the foundation for the later commercial produc-
tion of these papers in England and France. Later, many factories for
the manufacture of these papers came into existence. 9

The first large celloidin paper (with baryta coating) factory in
Germany was probably that built by Kurtz in Wernigerode (1890).

The emulsions cited (celloidin, zelloidin, and aristo) contained, in
addition to the colloid, silver chloride, silver nitrate, silver citrate or
tartrate, also free citric or tartaric acid.

The composition of these celloidin papers was varied to meet special
requirements. Professor Ferdinand Hrdlicka, of the Graphische Lehr-
und Versuchsanstalt, Vienna, manufactured patented special print

PRINTING-OUT PROCESSES

537

papers for weak negatives, obtaining a reduction of the gradation by
adding chromate to the silver chloride celloidin. E. Valenta 10 investi-
gated the effect of various admixtures on the gradation of print papers
and introduced for this purpose (1895) uranyl- and copper salts. He
softened too strongly contrasting emulsions by adding a silver phos-
phate emulsion. 11 At the same time Valenta investigated the developing
processes for prints on silver phosphate papers, 12 after having described,
in 1893, the development of collodio- and gelatino-chloride silver
emulsion papers with acid developers. 13

Another progressive step was the introduction of vegetable albumen
free from sulphur in the production of “protalbin paper” (with vege-
table albumen bodies soluble in alcohol), by Dr. Leon Lilienfeld, in
Vienna (German patent, April 21, 1897), which increased the per-
manency of the prints. Lilienfeld, however, discontinued the manu-
facture of this paper later, when he made the important invention of
ethyl cellulose as a motion picture film base and for artificial silk, and
when he became connected with the Eastman Kodak Co.

“Casoidin paper” (casein emulsion), made from casein preparations,
was invented by Dr. Otto Buss (1871-190 6) in Switzerland in 1903.
These emulsions were supplied in glossy and mat varieties, but did not
meet with favor ( Handbuch , 1928, IV (1), 193).

Positive prints on silver chloride papers usually show an unpleasant
brick-red tone. The beautifying (making them “look pretty”) and
deepening of the color tones (toning) was done with sulphur, which
with the silver formed dark silver sulphide.

In the forties this sulphur toning of paper positives, the result of
sulphide of silver in the hypo bath, formed by the liberation of sulphur,
owing to the decomposition of the hypo, was the only method known.
Old fixing baths gradually toned the prints brown.

Toning positive silver prints with gold salts was introduced between
1847 and 1850. The method of toning silver chloride prints with sel
d'or (sodium-auro-thiosulphate) , the use of which for toning daguer-
reotypes was suggested by Fizeau (1841) is supposed to have first
been introduced by P. E. Mathieu, who published his method in a
pamphlet entitled Auto-photographie in 1847. 14

Le Gray also recommended, in his booklet T raite pratique de photo-
graphic (Paris, 1850) , toning positive silver chloride prints with a solu-
tion of gold chloride in hypo. Humbert de Molard was the first to de-
scribe, in 1 85 1, separate gold baths (solution of chloride of gold and

PRINTING-OUT PROCESSES

538

chalk); he first immersed the print in the gold bath and after that
used hypo ( Handbuch , 1928, Vol. IV, Part 1). Waterhouse, of Hali-
fax, used in 1858 a gold chloride bath which had been made mildly
alkaline by adding sodium carbonate or sodium bicarbonate. In Jan-
uary, 1859, Maxwell Lyte reported to the French Photographic Society
the method of toning with gold chloride and sodium phosphate. The
chemist John Spiller (1833-1921), one of the directors of an English
chemical color factory, was the first to indicate the possibility of
admixing gold chloride with silver chloride collodion emulsions for
printing-out papers, which was the start of the much later commercial
manufacture of self- toning printing papers. For a biography and por-
traits of Spiller see Phot. Jour. (1922, p. 23) and Brit. Jour. Phot. (1921,
p. 673).

The first mention of the addition of gold salts to aristo paper was
made by the English scientists Ashman and Offord, who published
in the Phot. News of July 24, 1885, the admixture of gold combina-
tions to a gelatino-chloride emulsion, which accelerated the toning
process considerably. As a matter of fact, they did not recognize that
a subsequent toning process became thus superfluous. This seems to
have been first published by D. Bachrach three years later (Brit. Jour.
Phot., 1906, p. 319; 1908, p. 781).

In 1898 self -toning papers were manufactured in America with
gold chloride and ammonia (fulminating gold). In Germany, Oskar
Raethe introduced the admixture of the double salt, gold chloride-
barium chloride (1898), which was later adopted by Kraft and Steudel
in Dresden for their “cellofix” paper (Phot. Ind., 1925, p. 232). For
details see Wentzel (Handbuch, 1928, Vol. IV, Part 1).

E. de Valicourt 15 recommended, in 1851, the addition of lead salts
to the fixing baths, which also played a part later in the mixed toning
fixing baths for celloidin and aristo papers; he observed that hypo
mixed with lead acetate caused the formation of violet tones in silver
chloride prints, which Henderson 18 confirmed in 1862.

The way chemical processes combined in fixing and toning silver
prints with gold and hypo was shown in the intensive investigations
of Alphonse Davanne 17 and Jules Girard in their Recherches theoriques
et pratiques sur la formation des epreuves photographiques positives
(Paris, 1864).

Meynier introduced cyanogen sulphide, especially of potassium
thiocyanate and ammonium thiocyanate, into toning and fixing baths

MORDANT-DYE PROCESS AND UVACHROMY 539

in 1863 ( Handbuch , 1928, Vol. IV, Part 1 ). Thiocyanates have proved
their value in photographic practice, especially for gold toning baths
in modem emulsion print-out papers, not only in the separate toning
and fixing process but also sometimes as an addition to the combined
gold toning-fixing baths, in which hypo acts as the principal factor
in the fixation process.

Acid thiocarbamide gold toning baths were introduced by Helain 18
and Valenta. 19 Other improvements of the toning process belong to
recent times and need not be mentioned here. By introducing toning-
fixing cartridges and ready-mixed “toning baths” the manipulation
has been extremely simplified ( Handbuch , 1928, Vol. IV, Part 1).

Chapter LXXV. mordant-dye images on

A SILVER BASE; UVACHROMY AND ALLIED PROC-
ESSES

The basic idea in all processes of producing photographic mordant-
dye images is the conversion of the silver image into another substance,
which is capable of acting as a mordant on solutions of dyes. This action
deposits organic dyes on the image and colors the particles of the silver
image more or less strongly, about in proportion to the quantity of the
silver precipitate, and this creates half tone color pictures. Silver
bromide layers also develop and fix, but printed-out silver chloride
layers are used mostly.

The history of the mordant-dye process reaches far back into the
last century. The American Carey Lea was probably the first to try,
in 1865, to color a silver image with an organic dye in the sense of the
mordant-dye process, when he dyed a collodion negative, which had
been bleached with mercuric chloride with murexide, which is a purple
red dye prepared from uric acid (Phot. Archiv, 1865, p. 184). This
experiment was forgotten until thirty years later, when Georges
Richard (1896) published the general application of dyeing silver
images, which hold suitable mordant media, to the production of vari-
colored pictures (Compt. rend.., 1896, p. 609; Jahrbuch, 1915-20). This
information also led to no practical use, and only in the twentieth
century were practical methods found and perfected for producing
mordant-dye photographs, used especially in connection with three-
color pictures.

54 o MORDANT-DYE PROCESS AND UVACHROMY

The first use of mordant-dye pictures, which were colored directly
on silver iodide and used for three-color photography (diapositive on
glass), originated with Dr. Arthur Traube, in Berlin. He called his
process “diachromy” and took out a patent on it in 1906; the patent
application is accompanied in a practical manner by splendidly ex-
ecuted proofs. Traube converted fixed gelatine silver bromide images
on glass into yellowish silver iodide by means of an iodine-potassium-
iodide solution. He treated them with solutions of basic dyes, which
all combine well directly with silver iodide, or with the acid dyes,
eosin or triphenylmethane dyes. After the dye was washed out from
the gelatine, the silver iodide was dissolved out with a hypo solution
which contained tannin. Colored images remain, and red, blue, and
yellow pictures of this sort can be combined in three-color diaposi-
tives ( Jahrbuch , 1907, p. 103; 1912, p. 362; 1915-20, p. 171; Phot.
Korr., 1920, p. 103). These particular processes met with no lasting
success, because other silver combinations are more suitable for this
purpose than is silver iodide.

The Italian photochemist Namias pointed out in his speech be-
fore the Congress of Applied Chemistry in 1909 that a silver image
which is changed by the Eder-Toth lead intensification to lead ferro-
cyanide and silver ferrocyanide absorbs many dyes very satisfactorily
from their aqueous solutions; for instance, chrysoidine, rhodamine,
methylene blue, victoria green (Brit. Jour. Phot., Col. suppl., 1909,
p. 68; Jahrbuch, 1910, p. 525; 1915-20, p. 172).

Namias also tried toning with copper (1909), but, as he states him-
self, with little success; he had not yet recognized the advantage of
copper ferrocyanide for the mordant-dye process. The following
articles by Namias refer to the history of the invention of mordant-
dye pictures: “The Fixation of Coaltar Dyestuffs on Metal Compounds
by Which the Silver Image Is Substituted” ( International Congress
for Applied Chemistry, London, 1909); “The Fixation of Colors on
Copper-Ferrocyanide Images and Its Application to Trichromy”
(International Congress of Photography, Rome, 1 9 1 1 ) . Here was men-
tioned the production of red diapositives by fixation of fuchsin red on
copper ferrocyanide. Biography of Namias and further details are
given in Chapter XCVI.

It is to Dr. Traube’s credit that he recognized the great advantage
of copper ferrocyanide as mordant for dyes. Somewhat later Crabtree
and Frederick E. Ives made similar observations. Traube based on this

MORDANT-DYE PROCESS AND UVACHROMY 541

an excellent process for producing three-color diapositives true to
nature. He found in 1916 that the well-known copper toning bath
(potassium ferricyanide, copper sulphate, and potassium citrate, tar-
trate, or oxalate) which deposits on metallic silver images a reddish
brown precipitate of copper ferrocyanide (with silver ferrocyanide)
is especially suitable for the production of mordant-dye images. Traube
founded the Uvachrome* Company at Munich and a branch at Vienna
for the exploitation of his process, on which he had several patents.
Beautiful specimens of the uvachrome process were exhibited before
the Vienna Photographic Society on November 9, 1920 (Phot. Korr.,
1920, p. 301). The name “uvachrome” is derived from the Latinized
name of the inventor, uva meaning Traube (grape).

The manipulation begins with the printing of the delicate diaposi-
tives on silver bromide celluloid films from three-color negatives, pre-
viously made on panchromatic dry plates behind orange, green, and
violet-blue color filters.

After development the diapositives are fixed, washed, dried, and
then immersed in the uvachrome bath, which consists of copper sul-
phate, ferricyanide of potassium, and tri-basic potassium citrate.

Transparencies and projection diapositives (lantern slides) produced
by the uvachrome process are extremely brilliant in color and more
transparent than autochromes, therefore very suitable for the repro-
duction of subjects dealing with art, the natural sciences, and technical
advertising.

Traube patented 1 his processes in England and America, 2 as well as
in Austria (patent No. 87,807). Priority for the English claim is dated
as of February 1, 1916, and for the other claims, December 3, 1918.
He had French patents and also others. In Germany his first patent
was contested on the ground of a previous publication of Namias. The
patent process before the German Patent Office resulted in the annul-
ment of the general claim for the use of copper baths in the production
of mordant-dye images.

The subject of a supplementary patent was the production of highly
transparent pictures. It was granted a German patent under the number
403,428 (“Verfahren zur Herstellung von Farbstoffbildern aus Kup-
ferbildern”).

Not only copper ferrocyanide but also cupric thiocyanate may be
used for the mordant-dye process. F. J. Christensen transformed the
silver image into cuprous thiocyanate, for instance, bleaching the silver

PHOTOGRAPHIC TRACING METHODS

54 *

image in a bath of copper sulphate-potassium thiocyanate, potassium
citrate, and some acetic acid (German patent No. 319,459, September
7, 1918; English patent No. 132,846, 1918; Phot. Korr., 1919, p. 274)
and dyed them with acid rhodamine, fast green, and so forth. This
was followed by many other varieties of mordant-dye images, which
are described in Handbuch (1926, IV (2), 412).

These processes were used profitably not only in three-color pho-
tography (as represented by the uvachrome method) but also for
toning diapositives and especially motion picture films.

Chapter LXXVL printing methods with

IRON SALTS; PHOTOGRAPHIC TRACING METHOD
(BLUE PRINTS, ETC.); PLATINOTYPE

The sensitivity to light of certain iron salts (iron oxide salts),
especially iron chloride when mixed with organic substances, was
known long ago, as we have already mentioned in Chapter VIII.
Doebereiner (1831) was the pioneer in this field, since he discovered
the light -sensitivity of ferric oxalate (see Chapter XVII) .

Organic ferri-salts (especially citric iron oxide and potassium ferri-
cyanide), which were later so generally used in photographic printing
processes, were first successfully tried by Sir John Herschel in 1842, 1
and were described in detail by him; the printing processes founded
upon these salts, especially the cyanotype or blueprint process were
very important for the photographic tracing method.

Herschel observed and described the light-sensitivity of papers
coated with ferri-citrate and tartrate; he used in particular the brown
ammonium ferri-citrate, and he determined its photochemical reduc-
tion to the ferro-salt. He showed that the unexposed ferric salts do not
turn blue with potassium ferricyanide, but turn blue when the ferri-
salt is exposed. For the principle of the photographic, tracing method
of cyanotype see Handbuch, 1929, Vol. IV, Part 4. Potassium ferro-
cyanide gives by this method positive photographic tracings (Her-
schel), a method which was used by Pellet in his gum arabic iron
photographic tracing method in 1877 (see Handbuch, 1929, Vol. IV,
Part 4) . The great capacity for reaction of iron salt prints was recog-
nized by Herschel, who determined that the ferrous salt formed by

PHOTOGRAPHIC TRACING METHODS

543

light liberates metallic precipitates from solutions of precious metal
salts (silver, gold). With this he laid the foundation for the so-called
“argentotype” process of 1842, which in 1889 came up again with
small changes in England as “kallitype” process and was used later
also for the “sepia paper” (sepia iron tracing paper) introduced by
Arndt and Troost (1895) in practical form. The time for printing
argentotypes, as well as for photographic tracing, was greatly reduced
in modem times by the substitution of green ammonium ferri-citrate
for the brown salt by E. Valenta, 1897. 2

The different reactive capacities of ferric and ferrous salts toward
tannin, gallic acid, and so forth, led to the production of the so-called
“ink pictures” by ferrogallic printing processes, the beginning of
which can be traced back to Poitevin’s publication in the Bull. Soc.
frang. phot. (May 20, 1859). It led, about 1880, to the large-scale
production of ferrogallic prints with black lines on a white ground
( Handbuch , 1929, Vol. IV, Part 4) .

The fact, discovered by Garnier-Salmon, that ferricitrate changes
its hygroscopic properties in light (1858) met with little application,
although it was hoped to carry out powder processes and photographic
pigment processes with it. The effect was worse than by the powder-
ing process based on the light-sensitivity of the chromate sugar layers.

The above-mentioned idea of Herschel, however, to precipitate
precious metals by exposing ferric salts on those parts of the image
where ferrosalts form achieved great importance in artistic photog-
raphy when platinum salts were introduced into this process. Platino-
types are based on the use of a mixture of ferric oxalate with platinum
salts, preferably with potassium platinous chloride.

Platinotypes were invented by William Willis in England and
patented June 5, 1873 (No. 2,011), as a new “photographic printing
process.” He described his process as the coating of paper, wood, etc.,
with a mixture of ferric oxalate or tartrate with platinum, iridium, 3
or gold salts, which, after exposure under a negative, was immersed
in a solution of potassium oxalate or ammonium oxalate, in which the
picture was developed. The platinum salt he used was potassium
platinous chloride, or potassium platinum chloride, or platinum bro-
mide. Willis took out patents for improvement, July 12, 1878 (No.
2,800), for the addition of lead salts to the iron platinum mixture;
the exposed paper was developed in a mixture of potassium oxalate with
potassium platinous chloride. In his later patent of March 15, 1880

PHOTOGRAPHIC TRACING METHODS

544

(No. 1,117), Willis omitted all these additions of lead salts, etc., to
the sensitive layer; he increased the content of platinum salt in the
sensitive iron platinum mixture, and avoided thus the admixture of
this salt in the developer. For other changes and improvements in
platinum prints see Handbuch, 1929, Vol. IV, Part 4.

William Willis (1841-1923) was the elder son of the well-known
engraver of landscapes William Willis. After finishing his schooling
he worked in practical engineering at Tangyes, Birmingham, which
proved valuable to Willis in later years, enabling him to solve the
mechanical problems which arose when platinotypes were introduced
commercially. A new avenue opened to him when he entered the then
Birmingham and Midland Bank, where he rapidly advanced. He was
so well liked by the staff that when he left the bank they presented
him with a memorial and with a collection of works on chemistry. He
joined his father, who had invented the anilin printing process for
the reproduction of technical designs and drawings (Brit, pat., No.
2,800, Nov. 11, 1864). ( Handbuch , 1926, IV(2), 454).

Willis recognized that silver images were not permanent. He there-
fore decided to find a more stable metal, and chose platinum. Then
followed the wearing task of overcoming the many opposing diffi-
culties. He made innumerable experiments before he was able to
announce the process commercially. Finally, however, he earned his
well-deserved success with his platinotype printing. His first patent,
granted in 1873, carried the curious title: “Perfection in the Photo-
mechanical Process.” The mat surface, the neutral black tone, the
extraordinary permanence of the image, consisting of precious metal,
brought many supporters to this process; further improvements, such
as the sepia platinum prints and cold development, were patented in
1 878 and 1880. The Platinotype Co., founded by Willis, manufactured
platinum papers for the trade and was most successful in maintaining
their uniform quality. In later years, when the high price of platinum
caused difficulties, Willis worked out two similar processes, satista
paper, a silver-platinum paper, and palladiotype paper, of which the
substance of the image consisted of palladium.

Willis received the Progress Medal of the London Photographic
Society in 1881, and in 1885 the gold medal of the International Inven-
tions Exhibition. It was established that Willis was the first to produce
photographic prints in metallic platinum, and the first to employ plati-
num salts in combination with light-sensitive ferric salts and to use

PHOTOGRAPHIC TRACING METHODS

545

neutral potassium oxalate for developing these papers. He manufac-
tured not only mat black but also sepia platinum papers. One of his
chief assistants in the factory was Berkeley, who, among other things,
first proposed the use of sodium sulphite in developer solutions (Phot.
Jour., June, 1923).

During the late seventies, under the guidance of the inventor, beau-
tiful photographs were produced in London by the platinotype print-
ing method, but a reliable process for the individual preparation of
the sensitive platinum paper was not then known. Only through a
dissertation by the Austrian army officers G. Pizzighelli and Arthur,
Baron v. Hiibl, which had been awarded a prize by the Vienna Photo-
graphic Society and was published in 1882 ( Die Platinotypie, 2d ed.,
1883), was the process made generally available.

Captain Pizzighelli was at that time chief of the photographic de-
partment of the army technical administration, and Captain von Hiibl,
later field marshal and head of the Military Geographical Institute
at Vienna until the end of the World War, attended scientific lectures
at the Vienna Technical College. In their joint experiments they closely
followed Willis’s principle to prepare the platinum paper with ferric
oxalate and potassium platinous chloride and develop it in a potassium
oxalate solution. They had at that time no success with the use of
double salts of the ferric oxalate. In 1887, however, Pizzighelli found
the conditions under which ferric oxalate double salts were serviceable
in the preparation of platinum paper and observed that a black platinum
image is obtainable 4 by the addition of sodium oxalate to the prepara-
tory solution, whereby the reducing strength of the ferrous oxalate,
which had been formed by light, is increased to such a degree that no
further development is required. Captain Pizzighelli had meanwhile
been transferred to Bosnia, where he made the first experiments with
the “direct platinum printing-out process” without developing and
whence he sent the first successful “direct platinum prints” to the
author in 1887. Further improvements in platinum printing were the
result of investigations of A. Lainer, 5 Hiibl, 6 and others.

The first platinum papers were offered for sale (1880) by the
Platinotype Co., London. At first they were “hot developer papers”;
they were followed in 1 892 by “cold developer papers.” Later on,
platinum paper was also manufactured in Austria (Dr. Just, 1883)
and in Germany (Hesekiel, Jakobi, and others). In these commercial
platinum papers the strength and texture of the paper (smooth, more

546 PHOTOGRAPHIC TRACING METHODS

or less rough, thick water-color paper, pyramid-grain paper, etc.) were
given consideration and thus they met the demands of artistic photog-
raphy, especially for large pictures. It was soon noticed that although
the platinum papers were, to be sure, very beautiful, they were cold and
grayish black, so that ways and means were sought to vary the color
of platinum prints (partly by certain admixtures to the preparation
of the sensitive coating, partly by toning processes) into brown or
other shades ( Handbuch , 1929, Vol. IV, Part 4).

Platinum printing was employed before the World War chiefly
for the production of the highest class of portraiture and documentary
photographs, owing to its exquisite quality and permanency. The
author made photographs of contemporary portraits and historic paint-
ings for the government library by the platinum process. One of these
subjects was the statue of Paracelsus on the house at Salzburg in which
he resided.

Owing to the World War and the increased cost of platinum,
platinotype papers disappeared almost entirely from the professional
photographic field and were replaced by mat silver bromide and “gas-
light” papers.

Giuseppe Pizzighelli (1849-1912), son of an Austrian military sur-
geon, was educated at a military academy and came to Krems, near
Vienna, as lieutenant, in 1 869, where he devoted himself to photography
and often worked with one of his colleagues, V. Toth. He was ap-
pointed captain and director of the photographic branch of the mili-
tary technical administration in Vienna (1878). Here, in 1880, he
published an article on “fotantracografia,” invented in 1879 by Alex-
ander Sobbachi, in a book entitled Anthrakotypie und Zyanotypie.
In 1881 he worked jointly with the author on gelatine silver chloride
emulsions with chemical development, and in 1882 he wrote, with A.
von Hiibl, Platinotypie. In 1884 he was transferred to Bosnia as the
chief engineer, where he remained until 1893. This is where he worked
out his direct printing-out platinum paper. He was then transferred to
Graz (Styria) as major, later to Przemysl (Galicia), and he retired
as a colonel in 1895. He moved with his family to Florence, where
he built a villa in the Via Militare, continued his photographic studies,
and became president of the “Societa Fotographica Italiana.” He was
also an honorary member of the Vienna Photographic Society and
received many prizes. He died in Florence. We mention only his in-
dependent photographic works: Handbuch der Photographic fiir

PHOTOGRAPHIC TRACING METHODS

547

AmateureundTouristen (Halle, 1 8 9 1 ) ; in 1887 appeared Wis Anleitung
zur Pbotographie fur Anf anger which was read widely; he also wrote
various books in Italian and articles for the Bulletino della Societa
Fotografica ltaliana, which he edited. A biography and portrait may
be found in Phot. Korr. (1912, p. 199).

Baron Arthur von Hiibl was born in 1852, a descendant of an Aus-
trian officer’s family. He received his education at the military academy
and became an officer of artillery. He was sent to the technical college
at Vienna for further study of chemistry, and there he attended the
lectures on photochemistry by this author. In the laboratory for tech-
nical chemistry he worked out a method of fat analysis with iodine
(Hiibl’s iodine number), and then joined Pizzighelli in the study of
platinotype.

Hiibl entered the technical branch of the Military Geographic Insti-
tute in Vienna and modernized its photographic management, at the
same time devoting himself almost entirely to photogrammetry. He
wrote numerous works on photographic procedure, for instance, silver
bromide collodion (1894); the development of gelatine silver bromide
plates after dubious exposure ( 1889) ; silver prints (1896); three-color
photography with special regard to three-color printing and photo-
graphic pigment pictures in natural colors (1897), all of which were
issued in several editions. He also wrote Die Reproduktionsphoto-
grapbieim k.und k. Militdr geograpbiseben Institute (1889) ; Diephoto-
grapbischen Reproduktionsverfabren (1898), and numerous scien-
tific articles, which are reviewed in the Jahrbitcber. He introduced and
advanced the stereoscopic measurement process invented in Germany
at the Military Geographic Institute. As colonel, he equipped the new
building of the institute. During the World War, Hiibl, who had now
been advanced to the rank of a Lieut. Field Marshal, directed the enor-
mous distribution of maps for the army and managed the technical
section splendidly.

He also published works on sensitometry and the combination of
neutral tint wedges with color light filters ( Handbuch , 1930, Vol. Ill,
Part 4) .

After the collapse of the monarchy the temporary wave of com-
munism in Vienna also attacked the Geographic Institute. The de-
struction of the army destroyed respect for the authorities and also for
the authority of the last commander of the institute, Lieutenant Field
Marshal Kaiser. The workmen elected soldier’s councils, who demand-

548 PHOTOGRAPHIC TRACING METHODS

ed and forced the resignation of the chief. They joined the dangerous
communistic regime which had formed and which used the presses of
the institute for printing its placards. The authorities later regained
control, and the communistic element was eliminated. But the new
Republican government took no interest in the institute, and the Min-
istry of War recommended that it should be liquidated and completely
dismantled. A conference was held at the War Department, to which
were invited army officers, professors of geography and cartography,
reproduction technicians, and others. The majority of those present
supported this author in his recommendation for the continuation of
the institute and its transfer to the Ministry of Public Works. This
proposal was accepted, and the institute became the now greatly re-
duced Cartographic Institute of the Republic; its pioneer work and
numerous contributions to science and the arts being thus ended. 7

Notwithstanding the post-war troubles, foreign countries watched
these proceedings, and in 1920, when the confusion was at its height,
the ambassador from Brazil to Vienna engaged Hiibl and a selected
group of assistants, in behalf of his government, for the purpose of
making a survey and topographical maps of his country. The com-
pany departed in September, 1920, for Rio de Janeiro, but met with
great difficulties in their work. After four years Hiibl returned, suffer-
ing from troubles brought on by the climate. In his later work he was
able to employ what was left of his research laboratory at the Carto-
graphic Institute, but he retired in 1930, broken in health. The surplus
inventory of the old laboratory was transferred to the collection of the
Graphische Lehr- und Versuchsanstalt.

Among other honors, the degree of honorary doctor was given to
Hiibl by the technical college in Vienna. He was also an honorary mem-
ber of the Vienna Photographic Society, where he had been a member
of the board of management for many years.

Chapter LXXVIL FOTOL PRINTING (1905)
AND PRINTING PHOTOGRAPHIC TRACINGS tBLUE-
PRINTS, BROWN PRINTS, AND OTHERS] ON LITHO-
GRAPHIC PRESSES (1909)

“Fotol” printing, or “cyanotype gelatine” printing, belongs to the
group of photographic tracings and is based on squeegeeing ordinary,
unwashed cyanotypes (blueprints) on moist gelatine layers; this makes
it possible to obtain with greasy printer’s ink several impressions of the
tracings, in which the original negative blueprints appear as positive
prints in black lines on a white ground.

This process was invented in 1905 by Adolf Tellkampf and Arthur
Traube. Tellkampf continued to apply himself successfully to im-
provements of these photographic-tracing methods ( Handbuch , 1929,
Vol. IV, Part 4). He was not a chemist by training, but nevertheless
developed his photographic processes with a practical understanding
of the scientific problems.

His co-worker in working out fotol printing was the photochemist
Dr. Arthur Traube, the well-known joint inventor of the first pan-
chromatic sensitizer, ethyl red, and inventor of the uvachrome proc-
ess. The German patent for fotol printing granted to Tellkampf and
T raube bears the date of August 1 o, 1 905 (No. 2 o 1 ,968 ) . The inventors
coined the name “fotol printing.”

L. P. Clerc, in his book La Technique photographique (1927, II,
564) credits the brothers F. and J. Dorel (1905) with the invention,
but we cannot recognize this claim for priority, because no documen-
tary evidence is presented.

R. J. Hall, of London, called fotol printing “ordoverax” (1907),
but it is the same process. To this class belongs also “f ulgur” printing
of Peukert, at Munich ( Jahrbuch , 1911, p. 538). Henri Brengou
curved the gelatinized zinc plate around a press cylinder in order to
attain greater speed in printing (French patent, January 17, 1913, No.
265,760; Jahrbuch 1914, p. 399, with illustration of cylinder press).

On August 20, 1921, L. Daniel and R. Dumont received a French
patent (No. 539,639) for a gelatine mass, which gave a closer and more
intimate contact with the cyanotype. Nothing essentially new is con-
tributed to the patent of Tellkampf or the publications of Fishenden
and August Albert on the subject.

DIAZO COMPOUNDS

55 °

Fotol printing is a valuable method for the production of small edi-
tions of positive tracings with printing ink; but for the production of
larger editions it has been displaced by another invention by Tell-
kampf, for printing from tracings with chromated gum. Tellkampf
invented, in 1909, the making of photographic tracings on chromated
rubber in connection with an acid developer containing glycerine; in
this process those parts of an image on a zinc plate which were washed
out by this development take the rolled-on printer’s ink and can be
used like flat zinc plates, from which can be printed much larger edi-
tions on a lithographic press than it is possible to print with the fotol
process.

These tracings printed by lithography (the method of printing from
flat zinc plates without photography) have become the common prop-
erty of all larger establishments for printing photographic tracings.
They often employ the second Tellkampf process in the analogous
form of the “Douglasgraph-process”; 1 details of this process are re-
ported in Handbuch (1929, IV (4), 220).

Chapter LXXVIII. photographic print-
ing METHODS WITH LIGHT-SENSITIVE DIAZO
COMPOUNDS: DIAZOTYPY, PRIMULINE PROCESS,
OZALID PAPER

Diazo compounds are organic compounds which contain two nitrogen
atoms in a particular combination. They form a large class of substances
of special scientific and technical importance. These compounds, which
are also capable of forming numerous dyes, were discovered by the
chemist P. Griess in 1 860. Diazo compounds usually decompose very
easily (on heating and sometimes when exposed to light, whereby the
nitrogen is displaced). They very readily react with certain other
organic compounds (amines, phenols, etc.) to form fast dyes.

The light-sensitivity of diazo compounds can be employed in the
production of photographic prints which are called “diazotypes” on
paper and cloth of all kinds. A photographic process of this kind was
invented by Dr. Adolf Feer (German patent, December 5, 1889).
His diazotype paper, after five minutes’ exposure in sunlight, formed

DIAZO COMPOUNDS

55i

an insoluble dye on the exposed parts; the prints were fixed by washing
in water. This process met with no practical application.

Of greater importance were the primuline processes, which were
patented in Germany by Cross and Bevan, September 2, 1 890. Accord-
ing to the choice of reactive organic substances, the inventors obtained
red or orange colored and brownish-black prints (positive images from
positive copies) . The primuline process was the precursor of later
printing processes. There followed Andresen (1894), Schon (1899),
and Homolka ( Handbuch , 1926, Vol. IV, Part 2, and 1929, Vol. IV,
Part 4) .

The most notable success in the use of light-sensitive diazo com-
pounds was achieved by Gustav Kogel, when he found in the diazo
anhydrides a new group of light-sensitive and more stable substances,
which he used for the production of positive photographic dye pic-
tures. Thus, he created the widely used modern photographic-tracing
process which he called “ozalid process.” In order to produce these
photographic-tracing papers commercially he joined the dye works
of Kalle at Biebrich on the Rhine, which took over his German patents
of June 1, 1917, and November 20, 1920, on the dry-photographic-
tracing paper process. The development of the diazotype paper, which
has been exposed to light under the copy to be reproduced, is carried
out by fuming it with ammonia, without the use of wet baths of any
kind. This process which produces in the most simple manner positive
photographic tracings from reddish violet to black brown in color,
has displaced almost all other photographic-tracing processes, with
the exception of the photomechanical methods. The oxalid paper
factory in Biebrich has become the largest manufacturer of photo-
graphic-tracing paper in the world. 1 The foundation of later printing
processes with diazo compounds can be traced to Feer, Cross, and
Bevan.

Gustav Kogel, born 1882, at Munich, after passing his early studies,
joined the Benedictine Order in Brazil. He' continued his studies in
Pernambuco, Rome, and Leyden. He devoted himself to photography,
for instance, to reflectography (Breyertypy, see Ch. XL) in which he
employed the Eder-Pizzighelli gelatine silver chloride papers (typon
process).

Kogel introduced the use of ultraviolet fluorescent light in palimp-
sest photography ( Sitz.-Ber . preussisch Akad. d. Wissensch., 1914),
and later, in criminal investigation photography; he also experimented

CHROMATES

55 *

in the bleaching processes for the production of color prints. Kogel’s
ozalid process is reported above. During the World War he worked
at the Technical College at Munich; in 1922 he received the degree of
Doctor of Technical Science from the Technical College at Vienna.
After the war, the Benedictine Order to which he belonged was partly
dissolved, and Kogel left it. Since 1921 he has been professor of tech-
nical photochemistry at the Technical College in Karlsruhe.

Chapter LXXIX. discovery of the photo-
graphic PROCESSES WITH CHROMATES BY PON-
TON (1839) AND OF THE LIGHT-SENSITIVITY OF
CHROMATED GELATINE BY TALBOT (1852)

Vauquelin discovered in 1798 that chromic acid forms with silver
a carmine red salt which turns darker in light. Professor Suckow was
the first to observe, in 1832, that chromic acid salts mixed with organic
substances are light-sensitive even in the absence of silver. But it was
not until after the invention of the daguerreotype and much experi-
menting with light-sensitive salts that the Englishman Mungo Ponton 1
attempted, in 1839, evidently following Vauquelin’s statements, to
employ the light-sensitivity of silver chromates photographically. He
observed during his experiments that paper dipped in bichromate of
potassium (even in the absence of silver salts) was colored brown by
the rays of light. Ponton described these experiments in 1839 in his
report to the Royal Society of Scottish Artists. 2 The image was “fixed”
by mere rinsing, because salt colored by the sun becomes insoluble
in water ( Handbuch , 1926, Vol. IV, Part 2).

These statements prove that Ponton discovered the change of color
of the bichromated paper, although his conception of the nature of
the chemical reaction was quite incorrect. Ponton failed to realize
the much more important light-sensitivity of mixtures of potassium
bichromate with gelatine, rubber, etc. This discovery was not made
until later. 3

Becquerel tried to improve Ponton’s process and worked along the
lines of using starch paste and treating the chromate image with iodine,
in order to make the print clear and more visible {Comp, rend.., 1840,
X, 469).

CHROMATES

553

Hunt’s experiments (1843) to find 4 a better printing-out method
on paper by the use of a mixture of potassium bichromate and copper
sulphate (so-called “chromatype process”) led to no practical results,
nor did his “chromo-cyanotype” process, in which Hunt coated paper
with a mixture of potassium bichromate and potassium ferricyanide. 5

Talbot was the discoverer of the light-sensitivity of a mixture of
potassium bichromate and gelatine. He took out an English patent
on October 29, 1852, for the production of photographic etchings
on steel by the aid of this chromate mixture and published his method
in detail in the Comp. rend. (1853). He published the fact that chro-
mated gelatine becomes insoluble in light, 8 that is, it loses its capacity
of swelling in cold water. In this particular article, which is entitled
“Gravure photographique sur l’acier,” Talbot describes the light-sen-
sitive coating as a glue solution with potassium bichromate, with which
he coated a polished steel plate and dried it over an alcohol lamp; he
laid his diapositive on the coated side, printed a few minutes in the
sun, until a visible image appeared “yellow on brown background.”
The plate was then washed with water, after which the light image
(after Talbot’s detailed description) “appeared somewhat prominent,
since the water washed away the chromium salt from the parts affected
by light and swelled the glue coating somewhat.” Talbot etched
through the coating with a solution of platinum perchloride. In order
to get a half tone effect, Talbot interposed fine black gauze between
the diapositive and the coated layer, thus laying the basis for the later
screen process; he remarked that photographic prints on zinc and
photolithographs could also be obtained by this process, and mentions
this in his patent description.

Talbot’s observations on the property of chromated gelatine to swell
in water after exposure to light were utilized by Paul Pretsch (1854),
of Vienna, for a gravure process. He coated a plate with glue, potas-
sium bichromate, and silver compounds, exposed to light, washed in
water, and electrotyped or stereotyped the relief thus obtained. His
English patent (No. 2,373) is dated November 9, 1854; Pretsch did
not receive his French patent until July, 1855.

POITEVIN DISCOVERS COLLOTYPE AND PIGMENT PRINTING ( I 855)

The Frenchman Alphonse Louis Poitevin achieved great merit for
introducing photography with chromates. He studied the reaction of
chromates with organic substances in light very successfully and in-

CHROMATES

554

vented collotype (1855) as well as pigment printing. At first Poitevin
took out an English patent, December, 1855, for a new photographic
printing process, which in its specifications presents the principles of
collotype.

In his patent Poitevin recommends a mixture of “albumen, fibrine,
gum arabic, gelatine, and other similar substances with potassium
bichromate” to print an image on this coating, to dampen the plate
and roll it up with greasy ink, “which only adheres to the parts exposed
to light.” The print thus obtained could remain on this first produced
image coating or it could be used in the manner of lithographs by
transferring to different bases, like lithographic stones, metal, glass,
wood, and so forth, for the production of pictures. Poitevin goes on
to remark in this description of his patent that colored prints could
be obtained if a dye (pigment) were added to any of the above-
mentioned mixtures and the portions not changed by light were washed
away after exposure.

Poitevin exhibited photographic prints made according to this
patent 7 at the Paris “Exposition Universelle” in 1855. These methods
and the principles expressed in the patent description undoubtedly
represent the foundation of collotype and of pigment printing, and
we must honor Poitevin 8 as one of the distinguished inventors of these
photographic methods, next to Talbot and Pretsch.

Alphonse Louis Poitevin ( 1 8 1 9-8 2) 9 studied chemistryand mechanics
and received a diploma in 1843 as a civil engineer. He entered the
government service as chemist at the “National Salt Mines in the
East,” where he commenced his photographic experiments in 1848.
His first result was the “galvanography” on daguerreotype plates,
then he found a photochemical engraving process on metal coated
with gold, also one for daguerreotypes, for which he received the
silver medal of the Societe d’Encouragement des Arts. He entered the
employment of the factory of Pereire, in Lyon, in 1 850, as engineer and
went to Paris the same year. He devoted himself to a thorough study
of the photographic properties of chromated glue and discovered the
principles of collotype and of pigment printing, (French license,
August 6, 1855). Pretsch antedated him in the invention of photo-
galvanography by a few months only. He gave much attention to
direct photolithography in halftone on grained stone coated with
chromated albumen. In October, 1855, he erected a photolithographic
printing establishment; the enterprise did not succeed very well, be-

CHROMATES

555

cause Poitevin had not sufficiently mastered lithographic technique.
He therefore joined the famous Paris lithographer Lemercier, in Paris,
to whom he sold his patents, and in this roundabout way he was suc-
cessful in introducing his invention into practice. Later, Poitevin pub-
lished numerous important improvements in the field of photography
with chromates, photography with iron salts, photochromy with silver
photochloride, and so forth. For his invention of photography with
chromates (carbon prints) he received 10,000 francs from the fund
donated by the wealthy art lover the Duke of Luynes, but this irregular
income was insufficient to offset the considerable sacrifices required
to carry out his inventions, and in 1 869 he found himself again com-
pelled to take a position as civil engineer. He managed glass works at
Folembran, traveled to Kefoun-Theboul in Africa to exploit silver
mines, and after the death of his father returned to his birthplace
Conflans (Sarthe), where he lived modestly.

At the International Exposition in Paris (1878) Poitevin was honored
with the title “Collaborateur Universel” and was presented with a
gift of 7,000 francs and a gold medal in appreciation of his services for
the progress of photography. This money, however, seems never to
have been paid to him. 10 The Societe d’Encouragement des Arts, of
Paris, more than once gave him financial aid and finally granted him
12,000 francs, a prize founded by the Marquis d’Argenteuil. In 1880
he suffered an attack of brain trouble and died at Conflans. A monu-
ment to him has been erected at Saint Calais, the county seat of the
Department of Sarthe.

PRIZE COMPETITION OFFERED BY THE DUKE OF LUYNES

Poitevin’s photographic prints with printer’s ink exhibited in 1855,
imperfect though they were, attracted the attention of the Duke of
Luynes in Paris, who recognized in them the possibility of photo-
graphically producing permanent prints at a low cost. In order to
hasten the solution of this problem, the Duke offered, in 1856, money
prizes of 8,000 and 2,000 francs, respectively, and thus encouraged
the production of permanent photographic prints 11 (see Handbuch,
1926, IV ( 2 ) , 56).

The chemist H. V. Regnault, as chairman of the Paris Photographic
Society, prefaced the prize offer in the following words:

Of all the elements with which chemistry has acquainted us, carbon is
the most permanent, and the one which withstands most all chemical re-

CHROMATES

556

agents at the temperature of our atmosphere. The present condition of
old manuscripts indicates that carbon in the form of lampblack on paper
remains unchanged for hundreds of years. If we could therefore make it
possible to reproduce photographic images in carbon, we should have a
basis for their permanency, as we now have in our books, and that is as
much as we may hope for and wish.

This gave direction and impetus to the work on printing methods
with carbon or printer’s ink, which was not without influence on the
development of these methods, among which was pigment printing.
Up to 1 859 several entries for the Luynes prize were received: (1) from
Testud de Beauregard; (2) Gamier and Salmon; and (3) Pouncy.

Testud de Beauregard exhibited some good proofs, but for reasons
unknown broke off the practical demonstration of his method before
the commission, and his application was no longer considered. Messrs.
Gamier and Salmon successfully carried out a demonstration with a
dusting-on or powder method before the commission, and Pouncy’s
work was examined according to his directions by the commission,
since he was unable to appear personally.

Incidentally, the jury appointed by the Paris Photographic Society
declared that Poitevin was the real father of all these competing methods
by his new processes mentioned above.

Therefore Poitevin received the gold medal and Gamier and Salmon,
as well as Pouncy, were each awarded a silver medal.

FURTHER INFORMATION ON PIGMENT PRINTING

The Englishman John Pouncy exhibited in 1858 before the London
Photographic Society pigment prints (Jour. Phot. Soc., December,
1858, p. 91). At first he kept the method of production a secret, but
later divulged his method in detail. However, he took out at the same
time an English patent on this process (April 10, 1858, No. 780), from
which it appears that he used “vegetable carbon, gum arabic and
potassium bichromate” as coating in the preparation of his paper or
that he substituted bitumen or other pigments for carbon, in order to
obtain permanent photographs. That Pouncy’s gum prints were ac-
tually produced by this method is shown by a letter from his assistant
Portbury, published in the Photographic News (November 23, i860).
This pigment process with gum arabic and chromates had already been
mentioned, however, by Poitevin, and “Pouncy’s pigment process”
is covered by Poitevin’s patent specifications. 12 Nevertheless, Pouncy

CHROMATES

557

received part of the money prize of the Duke of Luynes’s contest,
owing to the excellent execution of his pictures. At any rate, Pouncy
may be considered the practical founder of printing with gum bichro-
mate.

Gamier and Salmon were considered in the distribution of prizes, 13
owing to a method of dusting-on the paper with chromates, sugar,
albumen or rubber and carbon powder, the description of which they
deposited on June 30, 1858, in the hands of the secretary of the Paris
Society and which was actually original. 14 The contest was extended,
and in 1862 Poitevin received the prize of 2,000 francs.

Notwithstanding these prize competitions of 1858, it was not pos-
sible to reproduce halftone negatives satisfactorily by Poitevin’s pig-
ment process; it was limited to the reproduction of outline drawings.

The reason for the destruction of the halftones in Poitevin’s pigment
process and similar methods, in which the image is created on the
coated surface and where the image is fixed by washing away the
unchanged particles, was first recognized by Abbe Laborde. 15

After Laborde had discovered why the halftones were destroyed in
Poiteviris pigment process, J. C. Burnett proposed a remedy in the
Photographic Journal (November 22, 1858, V, 84). He remarked that
the pigment paper was to be exposed through the back of the paper in
order that the pigmented portions of the image would adhere to the
base. This laid the ground for the use of transparent celluloid sheets as
carriers for pigment coatings; they were proposed in 1892 ( Jahrbuch ,
1892, p. 454), then in 1893, anonymously, probably Friedlein, of Mu-
nich, in Phot. Korr., 1893; see Hans Schmidt in Jahrbuch, 1909, p. 46.
This method was later applied by Robert Krayn (Neue Phot. Gesell-
sch., Berlin) for three-color photography with superimposed pigment
diapositives (1903).

INVENTION OF THE TRANSFER METHOD IN PIGMENT PRINTING

None of these methods in which exposure had to be made through the
paper resulted in the desired smoothness and sharpness of the picture,
which gave Fargier the idea to transfer the exposed chromate-pigment
coating face down on another base and thus to firmly fix the surface
image. Fargier’s pigment printing process, 10 patented in France, Sep-
tember, 1 860, consisted in exposing to light the gelatine pigment film
sensitized with chromate, then flowing collodion on it and immersing
the plate in warm water. The unexposed parts of the gelatine dissolved,

CHROMATES

5J8

while those parts of the pictures which had become insoluble by ex-
posure to light adhered to the collodion with all their detail and half-
tone structure. This detached itself from the original base and was
transferred to another, let us say, to a piece of paper.

Fargier repeatedly exhibited proofs of his pigment process before
the Paris Photographic Society (1861), and in 1862 he received from
it for his investigations in the field of pigment printing and for the in-
genious improvements of his method a prize of 600 francs (Bull. Soc.
franp. phot., 1862, p. 101).

An important step in the development of the pigment process was the
contribution of the Englishman J. W. Swan, who introduced the trans-
fer process. Joseph Wilson Swan (1828- 19 14) 17 improved the pigment
process and worked with untiring perseverance on the perfecting of
this method; thus, a large part of the practical success which was later
achieved in the pigment process was due to Swan’s labors, for it was
he who introduced the single and double transfer method of pig-
ment pictures to glass and paper (Handbuch, 1926, Vol. IV, Part 2).
He later established jointly with Mawson one of the first gelatine silver
bromide dry-plate factories in England. Swan also invented the elec-
tric-bulb lamp with a twisted carbon filament. He was knighted by
King Edward VII in 1 904 for his services in science and industry.

Swan devoted himself from 1864 to the pigment process, 18 which he
patented in England February 29, 1864 (No. 503). An excellent pig-
ment picture from the double transfer (rubber and paper) made by
him in 1866 is reproduced in the 1932 German edition of this History
(p. 779). Swan’s original prints of the early period have become very
rare, because his workshop and collections were destroyed by fire at
the end of the nineteenth century. W. Benyon Winsor, of London,
bought Swan’s patent and started the English Autotype Company,
which manufactured and sold pigment papers exclusively.

Adolph Braun, of Dornach (Alsace), at that time reproduced the
sketches of old masters at the Louvre and endeavored to represent the
various colors (brown, red, and gray) of the originals by a photogra-
vure process invented by Rousseau. Swan explained to him that he, by
his pigment printing method, could not only imitate the colors of the
originals but also produce the actual and exact paints which had been
used by the artist. He showed Braun a reproduction of an original
executed in a red crayon with actual red chalk (sanguine), and excited
his admiration for his method to such an extent that Braun used Swan’s

CHROMATES

559

process in making his reproductions of the works of the old masters,
which today have a world-wide reputation in all art schools.

Edgar Hanfstangl (son of the founder of the art publishing house
of Franz Hanfstangl) was the first to introduce pigment printing on a
large scale in Germany for art-print publishing at Munich; he also
manufactured pigment papers for the trade ( Handbuch , 1926, Vol.
IV, Part 2) and employed all modern photographic processes . 10

After this time the pigment process reached its height and became
one of the most important methods for reproducing art subjects and
also for artistic photography. Braun in Dornach, Hanfstangl in Mu-
nich, Autotype Co. in London, Goupil (Boussod, Valadon & Co.) in
Paris and others used this process.

The superior beauty of carbon prints on glass led to the application
of the carbon process for the production of transparencies and for
making duplicate negatives.

Swan also employed the pigment print process for the production
of copperplate printing plates on which rest two methods, namely, the
process of etching in which a pigment image (negative) acts as an
etching ground and the other, especially developed by Swan and
Woodbury, in which the relief of a positive pigment image serves as
a matrix for an electrotype (see Klic’s photogravure and photoelectro-
types in Ch. XC).

THE CHEMICAL BASIS OF PHOTOGRAPHY WITH CHROMATES

The chemical reaction of light on chromates in the presence of
organic substances, notwithstanding manifold practical uses of the
glue chromatic process, had been in the beginning hardly investigated,
which prompted the Photographic Society of Vienna to offer, in 1 877,
a prize of 140 ducats for a critical study on the light reaction of the
chromates on albuminoids, gelatine, and so forth. The prize was
awarded, in 1 878, to the competitive work of this author. 20 The tanning
action of the chromi-chromate (chromium dioxide = Cr 0 2 ) formed
by light was determined as the cause for the insolubility of the chro-
mated gelatines, and so forth.

The results of the investigations were published in the Phot. Korr.
(1878), and in a somewhat more detailed form as a separate pamphlet:
Vber die Reaktionen der Cbromsdure und der Chromate auf Gelatine ,
Gunmri, Trucker und andere Substanzen organischen Ursprungs in
ihren Beziehungen zur Chromatphotograpbie (Vienna, 1878). 21 A
short digest appeared in the Journal f. praktische Chevtie, (1879, XIV,
294).

5 6o gum pigment method

Since this pamphlet had been out of print for decades and was in
great demand, the Graphische Lehr- und Versuchsanstalt, in Vienna,
printed a new edition in 1916 (see also Handbuch, 1926, Vol. IV.
Part 2 ) .

Chapter LXXX. gum pigment method

Gum printing does not offer the precise reproduction of the fine de-
tails of pictures given by Swan’s pigment process, but splendid results
can be obtained by it for larger pictures with breadth of light and shade
effects. After Pouncy, the method had become forgotten; Bollmann’s
suggestions for gum-pigment pictures (1863) also met with no success
{Handbuch, 1926, Vol. IV, Part 2). Victor Artigue first directed in
1 889 attention to direct halftone printing method by recommending
a “velvet carbon paper” (Charbon velours) {Handbuch, 1926, Vol.
IV, Part 2). But this was no real “gum print.”

The modern revival of gum printing for pictorial photography was
begun by the French amateur photographer A. Roulle-Ladeveze, who
presented such prints first at the exhibition of the Photo Club, Paris,
in January, 1884. He was very successful with his pictures in sepia
and red chalk toning. He described his process in a pamphlet in 1894
{Handbuch, 1926, Vol. IV, Part 2). The English amateur Alfred
Maskell saw these prints by Ladeveze at Paris and brought them to
London in October, 1 894, for exhibition at the Photographic Salon of
that year. Later, Robert Demachy, of Paris, brought gum printing to
high perfection (exhibition at Paris Photo Club in 1895). He sent some
of his prints to the Photographic Salon, London, where one of them
was purchased by the amateur photographer Dr. Henneberg, of
Vienna, who also obtained information on the technique of the process,
and who introduced gum printing at Vienna. This gum-print method
was then called “gum-bichromate process” or “photo-aquatint.”
The earlier Ladeveze’s publication on gum prints was printed in
June, 1894, in the Photographische Blatter of the Vienna Camera Club.

This caused several members of the Vienna Camera Club to take
up experiments with gum printing, and they obtained good results,
but they have no claim to priority for the invention of this process.
When such claims were made, this author established the truth of the
matter in the Phot. Korr. (1914^. 1 16), under the title “Die Erfinder

PIGMENT IMAGES

5 6i

des Gummidruckes” (see also Handbuch, 1926, Vol. IV, Part 2).

The surprinting of several impressions in order to obtain better
halftones (multiple gum printing) was first published by Hiibl, March,
1898, in the Photogr. Blatter, Vienna. This method improved con-
siderably the gradations of tones. A question of priority raised by
Heinrich Kuhn was decided in favor of Hiibl {Phot. Korr., 1919,
pp. 100, 133; also Jahrbuch, 1915-20, p. 473).

Modem gum printing in France was well represented by Demachy
and Puyo, who call gum printing with a single gum-chromate layer
“French gum printing” and the method with two or three thin gum
layers and multiple printing the “Vienna method.” A retrospective
exhibition of gum prints was held at Paris in 1931 {Revue franpaise
de phot., 1931, p. 33). Dr. Henneberg, in Vienna, was the first to
produce two-color gum prints; then follow polychrome gum prints
after the three-color method.

The effective combination of platinotypes with gum printing was
first executed by Professor H. Kessler at the Graphische Lehr- und
Versuchsanstalt, in Vienna, and such prints were exhibited by the
institute at the Paris Exposition of 1900.

Gum printing later spread extensively in artistic photography to all
countries, was written about in numerous books, and was well repre-
sented at all exhibitions. Lately it has lost more and more ground,
perhaps because its procedure is somewhat troublesome and requires
more artistic skill than other printing methods.

Chapter LXXXI. pigment images by con-
tact; MARION (1873); MANLY’S OZOTYPE (1898);
OZOBROME PROCESS (1905); CARBRO PRINTS

A. Marion reported, in 1873, to the Paris Photographic Society that
exposed bichromate pigment paper prints when put in contact under
pressure with another piece of unexposed pigment paper would trans-
fer the insoluble light images to a certain degree onto the second paper.
He exhibited some of these “Mariotypes by contact” in the spring of
1873 before the Photographic Society of London. The process could
not compete, however, with the ordinary pigment process.

Thomas Manly, in England, improved the method in 1898 and was

OIL PRINTING

562

granted a patent (No. 10, 026) ; he called his process “ozotype” ( Hand -
buck, 1926, IV ( 2 ) , 281).

The working directions for ozotype were afterwards modified by
Manly himself, also by Hiibl, in Vienna (1903), H. Quentin, in Paris
(1903), and others, but the method failed to attain popularity or
practical application in photography.

In 1905 Manly described his “ozobrome” process, in which a gela-
tine silver bromide image is transferred by contact to pigment paper.
Baths containing potassium ferricyanide and bichromates were used.
The amateur photographer H. F. Farmer 1 worked out empirically new
directions for Manly’s “ozobrome” process in 1919 and coined a new
name for it, that is, “carbro” prints. The London Autotype Company
introduced this method on the market. H. F. Farmer’s process con-
sisted in the use of a solution of ferricyanide of potassium, bichromate,
potassium bromide, and potassium bisulphate, in which the silver bro-
mide image and the pigment paper is bathed and then put in contact
in a printing frame. After the reaction has taken place, which is
analogous to that of bromoil printing, a pigment image is obtained,
which can be developed in warm water. These methods were used
especially for enlargements.

Although H. F. Farmer cannot be designated as the sole inventor
of this method, he must be given the credit of having been the one
who made “carbro” printing a practical and easily workable method
(see Handbucb, 1926, IV(2), 312).

Chapter LXXXII. oil printing

Chromated gelatine when in contact with a negative exposed to
light and immersed in cold water will take up greasy colors on the
exposed parts. This observation was first made by Poitevin in 1855,
who produced such light images in greasy colors. This is the basis of
collotype, photolithography, and so forth.

The picture rolled up with printer’s ink can be used itself as original.
The Austrian photographer Emil Mariot of Graz (Styria), later con-
nected with the Military Geographic Institute, Vienna, described this
process in 1866 in the Phot. Korr. (1866, p. 79) and called it “oleo-
graphy.” He stated that the image could be transferred to another
paper and exhibited such pictures before the Vienna Photographic

OIL PRINTING

563

Society, but the time for such photographic methods had not then
arrived, and his method went into desuetude ( Handbuch , 1926, IV(2),
318).

W. de W. Abney was probably unaware of Mariot’s publication
when, in 1873, he described his “papyrograph,” which was nothing
else than the use of chromated gelatine paper exposed to light under a
negative, washed, rolled up with greasy ink, applied to printing on
plain paper ( Handbuch , 1926, IV(2), 331).

It was much later that another Englishman, G. E. Rawlins, of
Waterloo, Liverpool, again called attention to such greasy ink pictures.
He recognized, in 1904, the importance of this process as a new
vehicle for artistic photography, offering remarkable possibilities of
individual treatment and control and giving excellent results with
skill and experience. Rawlins 1 manufactured and sold gelatine papers
and other materials for the process. The gelatine papers were sensitized
by baths in a bichromate solution, exposed to light under a halftone
negative, and softened in water, after which the oil color was applied
by a roller ( 1 905 ) or a camel’s hair brush ( 1 906) . Rawlins published
his working procedure ( Photography , 1905, XX, 490) and propa-
gated the method by exhibits before amateur circles, where his oil
prints excited a great deal of attention. C. Puyo, in Paris, wrote the
booklet Procede Rawlins d I'huile (Paris, 1907), which was also trans-
lated into German, and after that time such oil prints were shown at
all photographic exhibitions.

No great inventive genius was required for the production of so-
called “oil transfers” on ordinary paper on a handpress and to obtain
in some degree a limited number of impressions (mat paper prints),
for it was really nothing but an inferior type of the long-known collo-
type printing. Of course, collotypes were printed from a glass base
on special presses, while oil prints required no special mechanical equip-
ment and were easily practicable for amateurs.

The transfer of oil prints was published in 1 87 3 by W. de W. Abney.
The modern transfer method in oil printing was introduced by M. R.
Demachy in Paris in the spring of 1 9 1 1 . Oil printing had the dis-
advantage that it demanded very strong light (daylight or electric
arc light); see Handbuch, 1926, IV(2), 331.

Bromoil printing therefore soon displaced it, for the gelatine silver
bromide paper required only a very brief exposure to light to give a
developable image and furnished a greater and better range of tone
gradations.

Chapter LXXXIIL BROMOIL PROCESS

Bromoil printing had its beginning in a curious manner; at first, in
theoretical deliberations. E. Howard Farmer, head of the photographic
department at the Regent Street Polytechnic, London, must be con-
sidered an original investigator of this and other similar methods. He
published in Eder’s Jahrbucb (1894, p. 6; and 1895, p. 419) the
observation that the gelatine film of an ordinary fixed silver bromide
image in a bath of 20 percent solution of ammonium or potassium
bichromate becomes insoluble (catalytic action) in the silver portions
of the print. The image of tanned gelatine obtained in this manner can
be developed in the same manner as pigment pictures in warm water
or can be colored like an oil print at ordinary temperature ( Handbuch ,
1926, IV( 2 ) , 293).

On this basis Riebensahm and Posselt invented their silver pigment
process (German patent, November 6, 1902), which was improved
by Gustav Koppmann in 1 907. Koppmann sold his process to the Neue
Photographische Gesellschaft, in Berlin, which patented it on February
27, 1907 (No. 196,769).

Along a different road Farmer’s discovery led to bromoil printing.
The Englishman E. J. Wall, 1 who lived at that time in London, pub-
lished in the Photographic News (April 12, 1907, p. 299) the follow-
ing idea:

Suppose we enlarge direct on to bromide paper and develop with a non-
tanning developer, such as ferrous-oxalate, we should obtain an image in
the ordinary way in metallic silver. If this image were treated with a bi-
chromate, the gelatine should be rendered insoluble in proportion to the
amount of silver present, just as though exposed to light. One would then
only have to dissolve out the unaltered bromide and the metallic silver
with hypo and ferricyanide to obtain an image in insoluble gelatine, to
which the ink or pigment should adhere precisely as in the original oil
process. If this would work, there is no reason why any bromide or gas-
light print should not be “oil-printed,” though I have no doubt that a
special emulsion would have to be used on account of the difference in
the gelatines.

Thus Wall invented bromoil printing without having engaged in the
actual execution of the process.

Wall’s basic idea led the Englishman C. Welborne Piper to practical
success in the introduction of the bromoil process. He made his results
public on August 16, 1907, in the Photographic News (p. 1 15), under

BROMOIL PROCESS

565

the title “Bromoil, the Latest Printing Process, a Remarkable Method
of Turning Bromide Prints and Enlargements into Oil-Pigment-
Prints.” These first directions for the production of such pictures were
rather complicated, but a few weeks later Piper announced a simplified
method (Phot. News., September 12, 1907). He treated the silver
bromide prints with a solution of potassium bichromate and potassium
ferricyanide, which forms ferrocyanide, according to the reaction
formulated by the author, which brings the bichromate to a much
more energetic tanning of the gelatine (formation of chromic oxide)
than the pure bichromate solution used by Farmer. Thus Piper became
the inventor of the modern bromoil process, which met with an
enormous success.

The year 19 1 1 brought another and safer method of bleaching and
tanning gelatine silver bromide pictures. F. J. Mortimer, in Amateur
Photographer, introduced a mixture of potassium bichromate, copper
sulphate, and potassium bromide as the best bleaching bath. By the use
of this mixture cuprous bromide forms on the silver portions of the
image, which in contact with the admixed bichromate, by energetic re-
duction to chromic oxide, brings about the tanning of the image in
the silver bromide gelatine. He published this improvement in his
Amateur Photographer (1911, p. 577). The bromoil process first
became popular in amateur circles, but later Continental professional
photographers also employed the process to great advantage.

The lawyer Dr. Emil Mayer, of Vienna, greatly advanced bromoil
printing with copper baths. Dr. Mayer, president of the Society of
Amateur Photographers, in Vienna, produced very beautiful pictures,
which he showed at exhibitions. He lectured on the process and wrote
a manual Das Bromolverfahren ( 1 st ed., 1912; Halle, 8th and 9th eds.,
1922; and an English ed., see also Handbuch, 1926, IV (2), 362).

Bromoil transfers were first publicized by C. H. Hewitt in the
Amateur Photographer (March 2, 1909, p. 199) which spurred De-
machy to the introduction of the analogous oil-transfer process in 1 9 1 1 .

Chapter LXXXIV. PHOTOCERAMICS, ENAM-
EL PICTURES WITH COLLODION, AND DUSTING-
ON METHODS

The Paris photographer Lafon de Camarsac first published, in 1855,
the fact that the silver image (collodion film) produced by the wet
collodion process (with development) should be treated with a gold
chloride or platinum chloride solution, in order to introduce gold or
platinum metal through chemical substitution in the picture film, which
when burned in on enamel gives darker shades of colors than silver,
which yields yellow tones (Contp. rend., XL, 1266; Dingler’s Poly-
techn. Journ., CXXXVII, 271).

Camarsac improved his process further and exhibited at the Paris
Exposition of 1862 “permanent photographic images on enamel and
vitrified porcelain, resembling Sevres paintings.” 1

C. M. Tessie du Motay and Marechal made later by the same process
photographic pictures on enamel (burnt in, in a porcelain kiln) which
they exhibited in Paris (Bull. Soc. franp. phot., March 3, 1865, pp. 59,
175 )-

Griine, in Berlin (1868), also employed the principle of burning
in gilt and platinized collodion images and used also iridium and pal-
ladium chloride solutions for the substitution of silver images in order
to change the tones of burned-in pictures on glass, enamel, and por-
celain (Phot. Mitt., V, 20).

A peculiar photochemical reaction of iron salts was discovered in
1858 by Henri Gamier and Alphonse Salmon (of Chartres). They
observed that ferric citrate, exposed to light, changes its solubility and
hygroscopic properties. 2 They based on this the first dusting-on pro-
cess, with which they produced prints on paper and on glass, which
they exhibited before the Paris Photographic Society. They called the
method “Procede au charbon.” They stated that ferric citrate on paper
as well as on glass showed less solubility in water, or in water containing
alcohol or glycerine, in the parts affected by light. They laid on the
print with a tampon pine soot or some other colored dry powder or
metallic salt which adhered only to the unexposed tacky portions, and
assisted the process by breathing on the print. The image was fixed by
rinsing in water, during which the iron salt dissolved and the dusted-on
powder adhered rather well to the paper. Finally, this carbon image
was coated with a rubber solution.

PHOTOCERAMICS

567

Poitevin employed this same principle in i860 and found that a
mixture of iron chloride and tartaric acid could also be used for dusted-
on pictures. He used this not only for ordinary powdered dyes but
also for metallic oxides (ceramic dyes). The dusted-on picture was
detached from its temporary base by flowing it with raw collodion
and burnt in on porcelain (Bull. Soc. frang. phot., i860, pp. 147, 304).

The dusting-on process with hygroscopic iron salts found little
application in photography. Much more successful proved the dusting-
on processes with the aid of hygroscopic gutta percha, honey, and
sugar mixtures with chromates. Gamier and Salmon, in 1859, aban-
doned the use of light-sensitive iron salts in the dusting-on process and
employed as hygroscopic layer a mixture of ammonium bichromate
and sugar (Bull. Soc. frang. phot., 1859, pp. 135, 357).

After this important discovery of the chromate dusting-on method,
it became obvious to employ metal oxides and ceramic dyes for dusting-
on images, which could be burnt in on enamel and glass in porcelain
kilns.

Dr. F. Joubert was the first to take up this idea, and he announced
a method with a layer of ammonium bichromate, honey, and albumen
(English patent, January 20, 1 860, No. 149) . He dusted with powdered
enamel, rinsed, fixed, dried, and burnt in, with due regard to certain
precautionary measures. 3 The method was announced subsequently
(Phot. News, 1862, p. 125) and was imitated in numerous varieties.

J. Wyard was the first, in i860, to exploit the chromate dusting-on
process commercially in London, and he produced by this method
lovely pictures with enamel colors on glass and English porcelain as
an article of trade.

J. B. Obernetter elaborated the dusting-on process with chromate-
gum (1864) (Handbuch, 1926, IV(2), 434). The amateur photog-
rapher Justus Leth, of Vienna, was especially successful, in 1 864, in
obtaining very beautiful photographic pictures on porcelain by the
dusting-on process. 4

At the present time photoceramics have become a branch of industry
which is practiced in Czechoslovakia, Saxony, France, England, and
other countries; often a kind of pigment process is employed.

Burnt-in enamel pictures found a singular application, worthy of
mention for its cultural historic significance, in that they are enclosed,
along with the customary documents, in the cornerstones of monu-
mental structures in order to preserve for later generations imperish-

568 AUER’S NATURE PRINTS

able photographs. This proceeding may have been instituted for the
first time in Vienna, when an excellent portrait of Emperor Francis
Josef I, burnt in on porcelain by J. Leth, was immured 6 in the corner-
stone of the Museum for Art and Industry on September i, 1871. A
duplicate of this photoceramic portrait was presented by the artist to
this author and is preserved in the collection of the Graphische Lehr-
und Versuchsanstalt, Vienna.

Chapter LXXXV. electrotypes; auer’s

NATURE PRINTS

The earliest attempts at nature prints were discussed in Chapter
IV. Not until the introduction of electrotyping by Moritz Hermann
von Jacobi (1801-74) i n 1837 was the molding of natural objects such
as plants made possible, that is, their impressions in copper by elec-
trolysis.

Jacobi was a physicist and an engineer. He devoted himself at first to
architecture at Konigsberg; in 1 8 3 5 he was called to Dorpat as professor
of architecture, where he investigated the action of the galvanic cur-
rent and invented electrotyping in 1837.

As early as 1836 De la Rive observed that copper deposited on the
copperplate of a Daniell element can be separated (stripped) and that it
represents a very exact reproduction of the surface of the plate. Jacobi
made the same observation in 1837 and built on it a process for mold-
ing various objects by the aid of the galvanic current. Murray found,
in 1 840, that nonconducting surfaces can be made suitable for galvano-
plastic reproduction (electrotyping) by rubbing them with graphite.

In 1837 Jacobi was called to St. Petersburg by the Russian govern-
ment. He introduced electrotyping there, wrote his book Die Galvano-
plastik in 1840, made great efforts to construct electromagnetic
machines, and made experiments on a large scale with electric light.
Jacobi wrote numerous scientific articles for the Memoirs of the
Academy of Sciences at St. Petersburg. He was accorded great honors,
became a member of the Russian Academy of Sciences, a state coun-
cillor, and was knighted.

ALOIS AUER EMPLOYS ELECTROTYPING FOR NATURE PRINTS

Court Councillor Alois Auer, director of the Government Printing

AUER’S NATURE PRINTS

569

Office at Vienna, is the inventor of the process for the use of electro-
typing in the production of nature prints. A conversation with several
members of the Academy of Sciences first interested him in making
experiments, June 14, 1849, with some fossils. The foreman of the
galvanoplastic department, Andreas Worring, made electrotypes of
them and delivered perfect impressions. Auer perfected this process in
its complete practical manipulation, and as early as 1852 he reproduced
numerous plastic objects, principally laces, plants, and insects, by
nature prints. He made an impression of the object in lead and from
this depressed matrix an electrotype was made for intaglio printing.
An impression from this electrotype on a copperplate printing press
naturally presents the same relief effect as the original, which was
molded into the lead, and therefore an exact facsimile is obtained.
For further details see Auer’s Die Entdeckung des Naturselbstdruckes
(Vienna, 1853); also Auer’s polygraphic illustrated journal, Faust
(1854). In 1853 there arose a claim for priority with regard to this
invention, when a notice appeared in some German newspapers that
the nature printing process, alleged to have been invented in Vienna,
had been discovered twenty years before in Copenhagen by goldsmith
Peter Kyhl and that a complete description of the method with forty-
six illustrations had been placed in the Royal collection of copper
etchings at Copenhagen. Auer replied to this by having printed at the
Government Printing Office, “Disputes about the Ownership of New
Inventions,” which was accompanied by a separate supplementary
volume containing twenty-five full-page illustrations reproduced from
Kyhl’s originals in facsimile: “A convincing proof of the impossibility
of comparing the process of the goldsmith Kyhl, owing to its de-
fects, with the nature printing of the Government Printing Office in
Vienna.” 1

Auer must indeed be called the inventor of galvanoplastic nature
printing, and he brought the method to a perfection which has not
been reached elsewhere. Two examples are shown in the 1932 German
edition of this History (p. 798) which illustrate the beauty of the
intaglio electrotypes from molds of leaves and permit the apprecia-
tion of the delicate structure. These are still more soft in the original
copperplate prints than in our halftone reproductions. Just as remark-
able is the nature print of a fem shown on page 800 of the 1932 German
edition.

The different many-colored leaves, blossoms, seaweeds, and so forth,

AUER’S NATURE PRINTS

570

Auer had imitated by the use of corresponding printing inks. By
rolling several colors on the copper printing plate, he produced
polychrome nature prints. A reproduction of this kind of nature print
in colors (1853) is shown in Table II at the end of the 1932 German
edition. We see anticipated in this the later color gravure.

Great astonishment was excited when Auer presented the first
proofs of nature printing, in February, 1853, through Anton Ritter
von Perger, to the Zoologic-Botanical Society, in Vienna. These prints
appeared very true to nature and were printed in their true colors
from the gravure plate. Several excellent works on botany were pro-
duced at the Government Printing Office by this method; for instance,
the Physiotypia Plantarum Austriacarum, by Pokorny and Ettings-
hausen (1856), 2 the skeletons of dikotyledon leaves, by Ettingshausen,
and various other works of a similar nature. Five more volumes of
physiotypia, which appeared in 1873, were probably a last attempt
to save this technique, which at one time showed so many well-earned
successes, from entire oblivion. The photomechanical processes, then
rapidly developing, had outstripped this nature printing.

auer’s biography

Alois Auer (1813-69) was apprenticed to a printer in his native
town of Weis, Upper Austria. According to Auer’s own story, he
devoted himself with great zeal to the study of languages, and his
extensive knowledge, together with examinations which he passed,
opened his road out of the composing room. In his twenty-fourth year
he became teacher of Italian in the college at Linz. In the same year
(1837) he submitted a petition to the “all highest source” at Vienna,
recommending the establishment of a Polygraphic Institute. His plans
were so well elaborated in technical detail that he was appointed
director of the Government Printing Office founded in 1 804. Formerly
this office was a small printing shop, and when Auer took it over it
had old wooden presses and forty-five workmen with little work on
hand. He introduced modem printing presses, worked out a typo-
metric system, and ordered type of many different ancient and modem
languages. He also introduced an electrotype foundry and proved to
be a constructive genius. His invention of nature printing made him
known everywhere.

He did not confine himself, however, to this method alone, but culti-
vated all the graphic methods known at that time. The exhibit of the

AUER’S NATURE PRINTS

57i

Government Printing Office at the Great Exhibition at London, in
1851, was so extensive that it received the great medal of the council,
the only award in Class XVII. Thus, Austria occupied a leading posi-
tion in the whole domain of the printing craft and of the graphic arts.

Auer published, in 1844, the Lord’s Prayer in 608 languages and
dialects in Latin characters, and in 1847 in their national alphabets;
Das typometrische System in alien seinen Buchstabengrossen (1845);
Geschichte der Hof und Staatsdruckerei (1851 ) and the polygraphic
apparatus of the same. For his services in promoting the printing of
works in oriental languages at Vienna he was appointed, by the
Emperor Ferdinand, a member of the Vienna Academy of Sciences.

His untiring diligence and zeal, as well as his intellectual ability,
created a great reputation for the establishment, which he directed
from 1841 to 1868. It flourished under his management and became
a world-renowned institution, where the progress of the graphic arts,
of the printing craft, electrotyping, and photography in connection
with the printing industry were co-ordinated, investigated, and pro-
moted. His versatility brought about his appointment as general direc-
tor of the government paper mill, and in 1862 he also took over the
management of the imperial porcelain factory at Vienna for two
years. Auer was held in great esteem by the government, was ap-
pointed court councillor, and was knighted with the title “von Wels-
bach.” He retired in 1868.

Auer’s many experiments were expensive, but the funds for them
at first were always at his disposal; and his printing plant, employing
about a thousand men, was extremely efficient. But the introduction
of nature printing caused a deficit. 3 For instance, the copperplates for
the Physiotypia Plantarum, of Ettingshausen, with its fifteen hundred
full-page illustrations, cost 40,000 florins, which the sale of the book
failed to cover. The government caused him to undertake many un-
profitable printing orders. The Academy of Sciences also was privi-
leged to have its printing done there practically without charge. In
1 849 a law gazette was created by the government and ordered to be
distributed with indiscriminate liberality to the governments of all
countries, free of charge. It was printed in the ten languages of as
many countries, with the German text opposite. It cost the mere sum
of one million florins. At the normal cost of printing, the production
was worth 1,600,000 florins and would have earned a profit, but under
the circumstances, it resulted in a heavy loss.

AUER’S NATURE PRINTS

572

The volume of these printed journals, which soon had no other
value than that of waste paper, had accumulated to such an extent from
1849 to 1852 that placed on top of each other they would have been
sometimes higher than Vienna’s tallest church (St. Stephen’s).

Auer also engaged in the invention of a speed printing press with
self-feeder, invented the production of paper from cornstalks, and
made many other improvements, which brought him no gain, but
more or less loss.

This unfortunate financial condition brought about attacks on Auer,
who, however, successfully defended himself, because after all he
showed a favorable balance sheet. The accounting department of the
court and Minister Baron von Bruck supported Auer, expressed to
him the appreciation of the government, and procured his appointment
as court councillor, with a salary of 4,000 florins.

At the height of his career Auer published a pamphlet printed as a
facsimile of his manuscript Mein Dienstleben (Part I, March, 1 860)
which reflected the appreciation extended to him by his patrons, Prince
Metternich, Count Kolowrat, Baron Kiibeck, and Baron von Bruck.

In contrast to this was the end of his government service, when the
minister of finance, Von Plener, treated Auer in a most disagreeable
manner. Plener was extremely parsimonious; Auer’s budget for the
institution was cut down 4 in an unfortunate and categorical, almost
insulting, way. Auer became greatly depressed by the cares of procur-
ing the funds necessary for the printing and publishing establishments;
these worries increased in the beginning of the sixties, when he found
it necessary to pay the accumulated bills. The harsh restrictions of the
finance ministry irritated him, and he felt impelled to write his defense
and accusations: Mein Dienstleben (Part II, 1864). He had it printed
privately and supported his statements with numerous official docu-
ments. The edition of the pamphlet, the submission of which to the
ministry was an official duty, on coming to the knowledge of the
ministry was ordered destroyed by the government before publication.
Auer was also forced, under threat of a disciplinary trial and loss of
his pension, to surrender his manuscript and galley proofs. Thus it
happened that his family knew nothing of this pamphlet, as his son
Dr. Carl von Auer stated to this author. Decades passed, and it seemed
as if the pamphlet had been forgotten. In 1919 the son of the printer
of the galley proofs of the booklet, which the father had retained,
gave the proofs to this author. With the consent of the minister, En-

AUER’S NATURE PRINTS

573

gineer Truka, who sympathized with correct historical presentation,
the pamphlet was reprinted at the Graphische Lehr- und Versuchs-
anstalt. It was printed for private circulation, with a preface by this
author, and sent to the Auer family, libraries, and other interested
persons. Further search revealed that a second complete copy, with
all the original documents, was preserved in the Imperial private
library, as the chief librarian, Court Councillor Dr. Payer von Thum,
related to this author. Evidently this “duty copy” was delivered before
it was known that the police were endeavoring to seize it.

When Dr. Carl von Auer learned of the existence of this copy, he
reprinted a small edition, edited by Payer von Thum. Both editions
have become very rare, but they belong to the most interesting docu-
ments of the battle of an inventive fiery spirit against bureaucracy.

On Auer’s i ooth birthday a memorial tablet was erected in his birth-
place in Weis (Upper Austria). His son Dr. Carl Auer von Welsbach
(1858-1929) invented the incandescent gaslight, named after him, as
the outcome of his investigation of alkaline earths in 1885. He invented
the osnium incandescent lamp and the pyrophoric cerium iron. 0

Alois Auer, the father, is of special importance in the history of
photography, owing to his invention of a nature printing process which
is practical and thoroughly elaborated, because of the closely connected
photoelectrotyping process, worked out by his employee Paul Pretsch.
Under Auer’s supervision was also produced the first Pretsch gravure
cylinder for rotary printing. Auer’s desire for the promotion of all
the reproduction processes of his time led to the acquisition of the
largest Petzval orthoscope lenses for reproduction purposes at that
time known in Vienna.

Auer’s nature printing method must be called the precursor of the
Woodburytype process. Woodbury employed the same principle
of relief molding in lead, but used photographic glue reliefs instead
of natural objects.

Chapter LXXXVI. electrotypes and

GALVANIC ETCHINGS

“Electrotypes” closely follow nature prints. They were invented
and made public by Franz von Kobell, at Munich, in March 1840.
He presented his first example of the electrotypic reproduction of
paintings in water color to the Bavarian Academy of Sciences, and
later (1842) he described his method in a pamphlet 1 with several illus-
trations. He painted with oil of spike and porcelain colors on metal
plates, with the design in strong relief, and electrotyped the plates.
Kobell obtained intaglio printing plates without etching, which could
be printed on a copperplate printing press and resulted in prints like
water color drawings.

Dr. Franz von Kobell (1803-75) became professor of mineralogy
at the University of Munich in 1826 and did splendid work in the
field of crystallography and mineralogy, as well as in analytical chemis-
try. He was also artistically inclined, published poetry in the Bavarian
dialect, 2 and joined K. A. Steinheil, in 1839, in photographic work.
The daguerreotype camera, constructed by them jointly in April,
1839, is on exhibition in the German museum at Munich (Zeit. f. wiss.
Phot., XXX, 212). Kobell also was quite familiar with the graphic
arts, which led him to the idea of electrography, which attracted
general attention and was introduced in the reproductive processes. 3
In his later years Kobell gave up his work in the graphic arts and re-
turned to his mineralogical studies.

Kobell published several examples of galvanography in his pam-
phlet Die Galvanographie ( 1 842 ) , which demonstrated that in painting
for electrotyping purposes the artist could work with a certain freedom;
notwithstanding all his technical skill, Kobell’s method never reached
practical perfection.

Independently of Kobell, but not until August 7, 1840, Jacobi ex-
hibited to the Russian Academy at St. Petersburg electrographs pro-
duced after the same principle as Kobell’s. 4 Hoffmann, in Copenhagen,
later announced this same method. The credit for having elaborated
this method as an artistic reproduction process and for having intro-
duced it into the art trade, belongs to two young Munich artists,
Schoninger and Freymann, who improved the process and published
in 1843 their first successful electrograph, a Titian portrait. Schoninger
joined Franz Hanfstangl’s establishment at Munich in 1 849.

GALVANIC ETCHINGS

575

The famous painter and lithographer Professor Franz Hanfstangl
(1804-77), worked in lithography from 1819 and established his own
lithographic establishment in Munich in 1834.“ In 1848 or 1849 he
installed Kobell’s electrography. He operated a large art publishing
business, where until 1853 a great number of originals and reproduc-
tions of art subjects were produced by this method and published.
Among these was an electrograph of Ruben’s “Columbus” measuring
19% X 26 inches and one of Fluggen’s “Court Decision,” which in-
cluded forty figures, measuring 21% X 28 inches. The competitive
success of the new methods of photomechanical reproduction induced
Hanfstangl, 8 in 1853, to discontinue his lithographic and galvano-
graphic establishment, although it was conducted with a high degree
of perfection. He started in that year his photographic art publishing
house at Munich, which he handed over to his son Edgar in 1868.

Electrographs were also produced by Auer at the Government
Printing Office, in Vienna, of which his Faust contains very nice ex-
amples, especially of the work of the painter Ranftl; one of these
original electrographs was exhibited in 1883. F. Theyer, 7 in Vienna
(1843), and Wiirthle, in Salzburg, devoted themselves temporarily
to this process, which around the end of the fifties of the last century
was discontinued, when the photographic reproduction processes were
taken up. Thus died out a technique 8 which no doubt represented
the first application of reproduction by electrotyping designs in relief
and is of interest as the forerunner of photoelectrotyping.

When the essential features of Kobell’s electrographing method,
in which drawings in relief are made on plain copper plates, electro-
types, and then printed on gravure presses, are compared with the
principle underlying the subsequent photoelectrotyping process, the
full analogy of this graphic art method with the later photomechanical
process is recognized. Kobell’s method reminds us especially of the
principle of Woodbury’s photoelectrotypes (the molding of a pigment
relief produced on a copper plate, washed in hot water) and secondly
in 1854 of Pretsch’s photoelectrotypes (the molding of a swelled glue
relief, hardening it, and using an electrotype from this relief as a
printing plate).

Electroetching, or the electroengraving process, rests on the phe-
nomenon that when immersed in an electrolytic bath, a metal plate
(copper, steel, etc.) dissolves rapidly at the positive pole. When such

GALVANIC ETCHINGS

576

metal plates are coated with an etching ground on which designs are
engraved and immersed in an electrolytic bath, etched plates are pro-
duced for relief or intaglio printing.

The first attempts to etch with a galvanic current were made public
by an Englishman, Spencer, in 1841. G. W. Osann, professor of
physics at the University of Wurzburg, invented independently the
same process and published it on June 7, 1841, in the Wiirzburger
Zeitung and in a pamphlet: Anwendung des hydroelektrischen Stromes
als Atzmittel (Wurzburg, 1842). A sample of an electrically etched
intaglio print may be found in Handbucb (1922, Vol. IV, Part 3).

Georg Ludwig von Kress devoted himself successfully to galvanic
etching and wrote a chapter on it in his book Die Galvanoplastik fur
industrielle und kiinstlerische Zwecke (Frankfurt a. M., 1867).

ETCHING OF PHOTOGRAPHIC IMAGES WITH GALVANIC CURRENT

As early as 1841 experiments were made with the etching of
daguerreotype plates by galvanic currents. Baldus was the first to cover
copperplates with a light-sensitive asphalt coating, and he etched them
in 1854 in a galvanic bath. La Lumiere of 1854 contains prints from
such Baldus etchings. Gillot, the Paris photoengraver, reproduced one
of these prints by “paniconography.”

Lyons and Mittwald used galvanic etching in 1 848 on copper and
brass cylinders for rotary printings. Later, photographic chromate
gelatine pictures were etched by this method on zinc, copper, steel,
and so forth.

Paul Schrott, of Vienna, reverted in 1920 to galvanic etching on
steel engravings for the production of matrices for postage and revenue
stamps, as well as for printing paper money and embossing dies pro-
duced by photography with albumen or glue chromates, as a substitute
for steel. He carried on his experiments in the Government Printing
Office at Vienna, where he was employed as engineer ( Archiv fur
Buchgeiverbe, 1920, LVII, 75; Jabrbuch, 1915-20, p. 540; Handbucb,
1922, IV, Part 3).

Chapter LXXXVII. photogravure with

ETCHED OR GALVANICALLY TREATED DAGUER-
REOTYPE PLATES

After Niepce’s early experiments in etching photographic asphaltum
images on metal plates and thus producing printing plates for graphic
reproduction, no progress ensued in the field of photomechanical
processes until the success of the daguerreotype awakened the atten-
tion of physicists. Several of them interested themselves in the problem
“to produce engravings on metal plates by the sole aid of the action of
light in combination with chemical processes.”

Two scientists, Dr. A. Donne, in Paris, and Dr. Josef Berres, in
Vienna, began experiments, independently of each other, to etch da-
guerreotypes for intaglio printing. To Berres belongs the priority of
publication, while Donne kept his invention a secret. Donne presented
to the Paris Academy of Sciences, early in 1 840, proofs of daguerreo-
type plates etched by him, but did not disclose his process. Daguerre
criticized the performance adversely and remarked at the session of
the institute that nothing approaching perfection could be obtained
by etching his pictures and printing them on paper.

At the same time Berres, professor of anatomy at the University of
Vienna, undertook similar experiments, and he produced, on April 5,
1840, his first fairly satisfactory etching of a microphoto of a section
of a plant photographed by Drummond’s calcium light. He announced
his successful results to the scientific world in the Wiener Zeitung of
April 18, 1840 (p. 737), and presented proof on April 30, 1840, of his
process to the Vienna Medical Society. Donne meanwhile allowed
nothing to be known of his method, while Berres published a booklet
on August 3, 1 840, Pbototyp nach der Erfindung des Professors Berres,
in which he speaks of his invention as offering usefulness in the arts and
sciences. This rare publication, with five sample illustrations, is pre-
served in the Graphische Lehr- und Versuchsanstalt, Vienna.

Berres’s etchings were later more deeply re-etched in further ex-
periments by the copper etcher Jos. Axmann, of Vienna, and worked
up to artistic perfection. 1 According to A. Martin, Berres etched at first
with nitric acid and later with electric current. 2 He worked untiringly
in the pursuit of his object and obtained very splendid results.

Grove, who had a great deal of experience in galvanic etching and
had worked out a method for galvanic etching of daguerreotype

578 PHOTOGRAVURE WITH ETCHED PLATES

plates, recognizes Berres as the first to publish a process of etching
photographic images, i. e., daguerreotype plates. Berres’s photogra-
vures were considerably better than Donne’s (Dingler’s Polytech.
Jour., 1841, XLI, 156).

Berres’s proofs demonstrate that he had progressed relatively very
far with his etching method, farther than any investigator working
along these lines, which is proven by the silver medal awarded him by
the Societe d’Encouragement. From his plates more than two hundred
impressions were printed. 3 These proofs (photos from nature) are, of
course, imperfect if judged by modern standards, but they show,
nevertheless, an exact reproduction of the outlines and somewhat also
the middle tones. They are remarkable achievements, if one considers
that the photographs were made in the camera obscura direct from na-
ture and were at once, without any transfer process, etched on metal,
a problem, which even to this day has not been satisfactorily solved.

Berres, however, spent no more time on his invention. He wrote: “As
a practicing physician, active professor, and journalist, I can no longer
devote more than passing moments to my creation and am forced, if
only for pecuniary reasons, to recommend it to and leave its cultiva-
tion to the craftsmen in the industry.”

Fizeau, as well as Claudet after him and then Grove (with photo-
gal vano-caustic etching in 1841), experimented with the etching of
daguerreotype plates.

A richly illustrated work comprising views of important monuments,
architectural subjects, and landscapes was published at Paris in 1842
by the optician Lerebours jointly with Rittner and Goupil, and Bos-
sange, under the title Excursions daguerriennes; vues et monuments
les plus remar quables du globe } Most of the full-page illustrations are
lithographed from daguerreotypes, some engraved on copper and
some etched by hand. There are others, however, which are produced
by Fizeau’s direct-etching process on metallic daguerreotype plates,
although in part very extensively worked over by a copperplate en-
graver. One of these which shows little retouching is reproduced in
halftone in the 1932 German edition of this History (p. 818), and
shows a bas-relief of Notre Dame. It is one of the few illustrations pro-
duced by Fizeau’s daguerreotype etching process. The page contain-
ing this illustration also gives a description of the procedure which
Fizeau used in transforming the daguerreotype into a gravure plate.
Fizeau etched the daguerreotype, produced on a silvered plate, with a

PHOTOGRAVURE WITH ETCHED PLATES 579

mixture of nitric and hydrochloric acid or with a warm solution of
copper chloride; the silver chloride formed in the etching, which re-
tarded the action of the acid, was removed with ammonia. The etched
plate thus obtained was altogether too shallow for printing, whereupon
Fizeau brushed the plate with linseed oil, wiped it carefully from the
surface, permitting it to remain in the etched parts. He then placed the
plate in a galvanic gold bath, in which the gold deposited only on the
clean surface. The gold top formed an effective protection for the
ensuing deep etching, which gave it the depth required for printing
on a copperplate press and for reproduction similar to a copperplate
engraving.

A very remarkable improvement in etching daguerretoype plates
was introduced by Paul Pretsch (the inventor of photoelectrotypes).
In the report of the Society of Arts, London, April 25, 1856, there is
a supplement by Pretsch, in which are announced new methods of
photographic etching on metal and which is accompanied by examples
of well-printed proofs. He had printed these in the Vienna Govern-
ment Printing Office. The article is headed: “Photogalvanographie;
or, Engraving by Light and Electricity.”

Pretsch’s method of etching daguerreotype plates consisted in coat-
ing them with a solution of gum arabic and then spraying them through
a fine-pointed glass tube, with an etching solution consisting of nitric
acid with sodium chloride and sodium nitrate. He obtained in this
manner a kind of retouching during the etching, and the plates thus
treated naturally showed a grain, which assisted the printing with
greasy inks. Pretsch therefore appears to be the inventor of the “spray”
method of etching, which was later used in etching machines for the
halftone process.

Since the original report has become very rare 5 and seems of great
importance, we reprint it here:

I have here another specimen of an etched daguerreotype picture, ex-
ecuted in 1854 in the same establishment. 9 A perfect picture is taken upon
silvered copper or upon real silver; the four edges are bent up for conven-
ience in manipulation, and the picture is fixed in the common way by
hyposulphite of soda. From this time until the end of the etching process
the plate must not be allowed to become dry. When fixed, the plate is
placed upon a stand in a horizontal position and warmed until what re-
mains of the hyposulphite of soda begins to evaporate. The solution is
then poured off, and the plate is washed several times with distilled water,

5 8o PHOTOGRAVURE WITH ETCHED PLATES

which must also be heated. Then a weak solution of gum arabic is poured
upon the plate, to which is added the etching mixture consisting of two
solutions, viz., one part of pure nitric acid 45 0 Beaume and eleven parts
of water; two parts of pure chloride of sodium, one part pure nitrate of
potash and forty parts of water. Of these solutions take nine parts of the
diluted acid and one part of the solution of salts. This etching liquid must
be well distributed over the gum solution upon the plate, which may be
done by using a pointed glass tube and by sucking in and blowing out
the fluid.

Not only chemical etching with liquids, but electrotyping also was
repeatedly combined with daguerreotypes. Fizeau was the first to try it
(1841) by copperplating a daguerreotype on a silvered plate and de-
taching the copper shell; this produced a copy of the daguerreotype
image which was not very suitable for printing. 7 Beauviere sought un-
successfully to improve this process (1850).

Poitevin observed in 1847, that with a copper sulphate (blue vitriol)
galvanic bath, copper will deposit first on those portions of non-fixed
daguerreotype plates which are covered with amalgam (but not as
rapidly on the silver iodide surface). He obtained in this manner a
detailed red copper image. 8

Poitevin used such a copper picture for printing. He fixed the gal-
vano-deposited daguerreotype plate with hypo, washed and dried it,
then heated it until the copper image began to oxidize. He poured
mercury on it, which was repelled by the copper oxide, but adhered to
the bright silver metal, laid gold leaf on it, which adhered to the amal-
gam and on renewed heating formed a gold top. Then he etched with
nitric acid through the copper surface and through the underlying
silver metal, so that only the gilt top remained. In this manner Poitevin
obtained his first “gravure photochimique,” in 1847, which was printed
as an intaglio printing plate on a copperplate printing press. It was sub-
mitted on February 7, 1 848, to the Paris Academy with other similar
etched plates.®

Poitevin’s etched plates reproduced only outline drawings and fell
short of Berres’s early work. Poitevin himself soon gave up this meth-
od and used, later, the chromate process. Gradually Berres’s process
and the other related methods were forgotten. The period of the
photomechanical printing process had not yet arrived. Interest in it
had not been awakened, since all attention was focused on the per-
fection of the photographic process proper.

Chapter LXXXV1LL INVENTION OF PHOTO-
ELECTROTYPES FOR COPPERPLATE PRINTING AND
TYPOGRAPHIC REPRODUCTION

PRODUCTION OF PHOTOGRAVURES BY PHOTOELECTROTYPES
FROM GLUE CHROMATE RELIEF IMAGES

All methods of photoelectrotyping rest on the principle of molding
a photographic relief picture and can be traced to the underlying
method of Kobell’s electrography. While Kobell produced graduated,
balanced relief pictures with a brush in a freehand manner on silver
plated copper plates and by a galvanic deposit obtained an intaglio
printing plate, in the photographic processes the relief picture was pro-
duced by the action of light. The invention of making a mold from
the reliefs which are produced photographically with chromated glue
or gelatine chromate and by a galvanic deposit, and their application
to intaglio and typographic printing must be credited to the Viennese
Paul Pretsch.

Paul Pretsch (1808-73 ) 1 was the son of the goldsmith Johann Pretsch,
of Vienna. He learned the printing trade (1822-27) at Vienna from
the master printer Anton von Haykul, in whose employment he re-
mained until the death of his father, in 1831. He worked his way to
Munich, Augsburg, Ulm, Stuttgart, Karlsruhe, and along the Rhine
to Cologne, from there to Brussels, Amsterdam, Hamburg, and finally
returned to Vienna (1839-41). He learned electrotyping for the print-
ing trade, went to Jassy (Rumania) as manager of a business, and re-
turned to Vienna, where Director Auer employed him in the Govern-
ment Printing Office as foreman, and, owing to his linguistic knowl-
edge, as proofreader. In February, 1850, he was ordered to study the
application of photography to the graphic arts, the Government Print-
ing Office being at that time equipped with an efficient photographic
studio where the Talbotype and later wet collodion processes were
employed. Here were produced fine photographic views of the city
of Vienna, Schonbrunn, and other places, which were exhibited with
great success. Pretsch was sent several times in 1850 as an expert in
forgery cases to London and Paris, and in 1851 as director of the affairs
of the Government Printing Office to the World Exhibition, London. 2
He made connections there which greatly influenced his future. After
nine months he returned to Vienna and elaborated his idea to electro-
type the relief picture of bichromated glue which had been exposed

582 PHOTOELECTROTYPES

to light and which had swelled in cold water, according to Fox Tal-
bot’s process. 3

In the late fall of 1854 he gave up his secure employment at the
Government Printing Office, Vienna, and went to England, where he
remained for nine years and carried out his ideas for linking photog-
raphy to the printing press. He is the inventor of what he called “photo-
galvanography.” He took out a British patent (No. 2,373), on Novem-
ber 9, 1854, under the title “Production of Copper and Other Printing
Plates,” which formed the basis for his French “privilege” of June 1,
1855, and for the Austrian patent of 1866, eleven years later. A later
English patent (No. 1,824) °f August n, 1855, entitled “Obtaining
Cylindrical and Other Printing Surfaces,” had as its subject the use
of a photoelectrotype copper cylinder for rotary printing on textiles.
Pretsch realized his ideas and experiments by their introduction into
practice and started, in 1855, at Islington, London, the Patent Photo-
Galvanographic Company. This company issued, in 1856, a serial work
Photographic Art Treasures, in large size, of which five numbers ap-
peared, each with four illustrated pages. This was the first periodical
devoted to artistic reproduction that was illustrated by a photome-
chanical process (in this case intaglio copper plates) . A large house was
rented, and the work was assisted by experienced copperplate en-
gravers, who retouched the plates. Numerous reproductions were
turned out in 1856 and 1857— many photographs taken from nature,
for which the photographer Roger Fenton made the negatives. The
company was dissolved after two years, and Pretsch carried on the
business alone. Although Fox Talbot had an old patent on an invention
for etching photographic images, he took no steps to prosecute
Pretsch for his infringement. The process which Pretsch employed,
the details of which are not within the limitations of this work, had
nothing in common with Talbot’s method of etching.

A young man named Campbell Duncan Dallas was assigned to the
position of managing partner, and Pretsch initiated him in all the de-
tails of the process, which otherwise were carefully kept secret. This
Dallas made himself extremely undesirable. As early as June 5, 1856,
he applied for a British patent in his own name (No. 1,344) on “Im-
provements in Chemical Preparations Applicable to the Photographic
and Photogalvanic Processes,” but he was unable to furnish the de-
tailed specification within the required time, and the patent was there-
fore not issued. This left Pretsch’s original patent standing as the only

PHOTOELECTROTYPES 583

valid one, but it also expired on February 2, 1858, because Pretsch per-
sonally had no money to pay the patent fee and the company for the
exploitation of his process had gone out of business. This made the
process public property, but it was protected in some measure owing
to the lack of knowledge for the manipulation of the method. Now
Dallas started the process on his own part and called it “Dallastypy.”
He went so far as to contest his teacher’s priority rights and to repre-
sent himself as the inventor. He refused to demonstrate, however, in
what his “Dallas” process differed from that of Pretsch. Subsequently
Dallas failed in his efforts to establish his fraudulent claims, because
outstanding experts like Anton Martin, in Vienna, Scamoni of the
Imperial Russian Bureau of Engraving, as well as Leipold (Pretsch’s
only pupil) of the Government Printing Office in Lisbon, and others
ranged themselves on Pretsch’s side (Phot. Mitt., 1874, II, 107; also
Phot. Korr.). Pretsch had meanwhile suffered mentally and physically
and was unable to plead his own case.

Major General J. Waterhouse wrote a most interesting and com-
prehensive survey on the history of photoelectrotyping and its inventor
Paul Pretsch for Penrose’s Pictorial Annual (191 1, p. 157; see also Le
Procede, 191 1, p. 161).

The 1932 German edition of this History (p. 825) shows a half-
tone reproduction of a photograph by Cundall and Howlett, London,
portraying English grenadiers at the time of the Crimean War. The
original reproduction, in Photographic Art Treasures (1856), was
about 8x10 inches. It is obvious that Pretsch required a great deal of
retouching by copperplate engravers for his photoelectrotype plates,
especially in the shadows, nevertheless the delicate middle tones must
be acknowledged as an accomplishment in photographic processes. At
any rate, the photogravure plates, though more or less re-engraved by
hand, were superior to similar products of that time and more artistic
in effect than Talbot’s later copper etchings. Since, however, Talbot’s
copper etchings required less handwork and marked a great advance in
the technique of photogravure, photoelectrotypes were displaced for
halftone pictures at the beginning of the sixties of the last century by
the etching process, while for line and map work photoelectrotypes
held their precedence.

At the London World Exhibition of 1862 Pretsch exhibited not only
intaglio photoelectrotypes but also “halftone” plates for typographic
printing, which had been made by the glue-chromate process and

584 PHOTOELECTROTYPES

electrotypes. The results were very mediocre, but they are worthy of
note as early attempts of utilizing the natural grain structure of gelatine
chromate layers. Pretsch received the only medal in this class of exhibits
for his prints by photoelectrotyping on gravure and typographic
presses. All this notwithstanding, he could not make a living in London
and had to contend with persistent worries and misery. He returned
to Vienna the following year, where he was very ill for a long time.
For several years nothing was heard of Pretsch’s invention, but in 1865
Die ungarischen N achrichten and the Neue freie Fresse printed the
news that Pretsch had succeeded, after numerous and laborious ex-
periments in 1864, in improving his process, and that he was giving all
his time and efforts to the production of copper plates for printing on
typographic presses. The principle of the production of photoelectro-
types for typographic printing consisted in making molds of the bi-
chromate images on a glue top, which had produced a swelled relief
picture in cold water. He endeavored to obtain the greatest possible
relief and separation of the swelled portions, because the reticulation
promoted the formation of halftones.

Pretsch also succeeded in interesting the English scientist De la Rue
(1815-89) in his invention, especially in his “photographic electro-
types.” De la Rue was well known by his work in astronomy, chemis-
try, and especially in the application of photography to the observa-
tion of astronomical phenomena. 4 He joined Pretsch temporarily, and
several landscapes and pictures of statues and paintings (electrotypes
in relief) were produced photographically, signed “De la Rue and
Pretsch.” But the connection met with no success. In 1865 Pretsch re-
ceived a subsidy from the Austrian government in consideration of the
importance of his invention and to enable him to perfect his experi-
ments. His process was also recommended for trial to larger institutions
issuing illustrated publications. He made experiments at the Military
Geographic Institute in the production of maps on typographic presses,
but his method was not practical for this purpose. Pretsch was now
thoroughly discouraged, but again he found employment at the Gov-
ernment Printing Office. His shattered health, however, kept him from
efficient work and from attaining satisfactory results, so that finally he
confined himself to proofreading.

Pretsch’s invention found many imitators. Dallas, in London, and
Negre, in Paris, 0 worked along the same lines (electrotypes from gela-
tine chromate plates in relief) . Negre seems to have been the first to

PHOTOELECTROTYPES 585

transfer the coarse-grained gelatine chromate images to zinc plates and
make them suitable for printing by etching them according to Gillot’s
“zincotype” process.

Poitevin also had the idea to model the swelled relief chromate glue
tops in plaster of Paris or to mold them for electrotypes and use them
as printing plates. He worked with the process, first invented by
Pretsch, without seeming to have had any knowledge of it and took
out a French patent August 26, 1855, for his “helioplastie” as he named
his process ( Handbuch , 1922, Vol. IV, Part 3). On the occasion of the
World Exposition of 1855 Poitevin exhibited several of his heliotypes
for relief and intaglio printing. Poitevin made no further progress in
this process, especially in the development of the halftone process.

Poitevin declared erroneously that his process of photoelectrotyp-
ing differed in principle from Pretsch ’s method, because he claimed
that Pretsch washed away the unexposed portions of the gelatine chro-
mate so that the exposed portions remained representing the image,
while as a fact he (Poitevin) used swelled reliefs (Poitevin, Traite de
/’ impression photo graphique sans sels d.' argent, Paris, 1862, p. 5). This
statement of Poitevin is, however, incorrect, because Pretsch also used
swelled reliefs, so that both processes were really identical. Pretsch,
having taken out his patent first, is therefore entitled to claim priority.
Pretsch arrived in London with his completed photoelectrotype proc-
ess in October, 1854, and at once took out a British patent, dated
November 9, 1854. Poitevin’s “brevet d’invention” is dated August 27,
1855; he was not granted a British patent for photoelectrotyping on
account of Pretsch’s priority. Pretsch defended his unquestionable
priority rights in an article in Horn’s Phot. Jour., 1857.

Pretsch’s photoelectrotyping process suffered because a swelled glue
relief had to be molded, in which the portions in relief were formed by
glue which had not been tanned; therefore the glue swelled greatly in
water, while the low portions were formed by the glue that had been
hardened by light. The portions in relief were naturally very easily
injured, which made it difficult to handle them.

After Pretsch’s death the process was further improved by his
former pupil and colleague Joseph Leipold, who was employed at the
Vienna Government Printing Office and later directed the Department
of Gravure and Photoelectrotyping at the Government Printing Office
in Lisbon. To him we are indebted for publishing directions for manipu-
lating Pretsch’s process in the Phot. Korr., 1874, p. 180.

PHOTOELECTROTYPES

586

Georg Scamoni, 8 chief of the photogravure and lithographic de-
partment of the Imperial Russian Bureau of Engraving at St. Peters-
burg in the seventies, also promoted photoelectrotyping from swelled
reliefs. He reported his success in results in his basic, beautifully illus-
trated Handbuch der Heliographie (St. Petersburg, 1872). He also
attempted to model gelatine chromate swelled reliefs in plaster of Paris
and wrote useful directions for the method.

Pretsch’s process of molding swelled reliefs for typographic print-
ing was used by Wegner and Mottu in Amsterdam, who published
prints in Phot. Korr. (1874), but Pretsch’s achievements remained un-
excelled.

The molding of glue reliefs (swelled process) in plaster of Paris,
which had appeared on the scene repeatedly (Poitevin, Eng. patent
No. 2,816, December 13, 1855; Handbuch, 1922, IV(3), 267, 832),
was again taken up by Gustav Re, of Jeletz (Russia), in 1878. He called
his process “helioprint,” but it was hardly practical as a graphic method,
although he presented good-looking proofs. This method continued to
make periodical appearances for industrial uses as in the production of
designs on ceramics, glazed tiles, and so forth, but only to disappear
again.

PHOTOELECTROTYPES FROM HARDENED GELATINE CHROMATE
RELIEFS PRODUCED BY WASHING OUT WITH WARM WATER

Fontaine, in Marseille, 7 in 1 862 changed Pretsch’s process by washing
out with warm water the gelatine chromate copperplates after ex-
posure, instead of producing swelled gelatine plates in cold water; the
method proved unsuitable in this form for the reproduction of the
middle tones.

Joseph Wilson Swan, to whom pigment printing is indebted for its
greatest advancement, invented a photomechanical method in which
the transfer process of the pigment image, shortly before invented
by Woodbury, played a role. He took out a patent (Eng. patent, No.
1,791) on July 6, 1865, on a “photo-mezzotint process,” in which pig-
ment images were transferred to glass or metal, developed in warm
water, and the hardened pigment relief electrotyped. He produced
thus halftones for lithographic and typographic presses, which could
be printed with ordinary greasy printing inks. This method, however,
never achieved its desired object; the results were unsatisfactory, owing
to the lack of grain formation in the halftones, and Swan soon turned
to other photomechanical methods.

PHOTOELECTROTYPES 587

INVENTION OF WOODBURYTYPES OR PHOTOGLYPTY

The photomechanical processes received a great impetus, especially
for the production of delicate halftone plates, from the work of Walter
Bentley Woodbury in the beginning of the sixties of the last century.
Woodbury (1834-85) was born at Manchester. He led a life of adven-
ture in his youth and went to the gold fields of Australia when fifteen
years old, but had no luck. He became a professional photographer in
1855. In 1859 he went to Java, where he successfully worked the wet
collodion process. He returned to England in 1863, where he devoted
himself to the development of photomechanical processes, took out
no less than twenty patents, of which the “Woodbury type” met with
enormous success. He died at Margate. 8

Woodbury 9 changed the relief method, probably without know-
ing anything of Fontaine’s somewhat similar, but very imperfect pro-
cedure, by coating the chromated gelatine on collodion film, exposed
from the back of a negative, then washed the exposed film (just as
in the pigment process) with warm water. Thus he removed the un-
changed gelatine on the portions not affected by light, so that the
raised portions, the relief, were formed by the chromated gelatine
hardened by the light. By this method of exposure to light all middle
tones were retained on the film, which was a decided advance over
Fontaine’s method. These reliefs were better able to offer resistance
to the mechanical pressure, as well as to chemical actions. Recognizing
this fact, Woodbury, with Ashton, took out a patent (Eng. patent, No.
2,338, September 23, 1864) in which he described the electrotyping
of such reliefs and the printing of impressions from these intaglio plates
with transparent ink (for instance, china ink and gelatine). In later
patents (January 12, 1866, No. 105; February 11, 1866, No. 505; May
8 , 18 66, No. 1,315; July 24, 1866, No. 1,918; and others) he improved
this invention and finally perfected his method, which was introduced
to the photographic industry as photoglypty, or Woodbury type. He
left the electrotyping of the pigment reliefs behind and turned to
molding his glue reliefs by hydraulic presses in sheets of lead producing
printed impressions with liquid gelatine china ink from these lead in-
taglio molds, in which the halftones of the pictures were obtained with
great perfection. Because of their softness, fine definition, and absence
of grain or halftone screen effects, Woodburytypes met the most se-
vere requirements. In the seventies Woodburytypes were made and
used extensively in England, France, and Belgium. The delicacy of

588 PHOTOELECTROTYPES

these reproductions and their durability are unexcelled. As late as 1884
many establishments for the printing of Woodburytypes (lead ma-
trices) were in full swing. The impossibility of incorporating Wood-
burytype illustrations in the text of periodicals and books, 10 however,
and the slowness of their production gave the ascendancy to gravure
(rapid-press printing), which displaced Woodburytypes toward the
end of the last century.

Woodbury patented, in 1872, a method of producing photographic
printing plates (by the Woodburytype process) for cylinders and
made them thus suitable for rotary printing (Eng. patent, No. 3,654,
December 4, 1872).

Woodburytypes, molded by hydraulic presses in lead sheets, furnish
fine impressions, printed with transparent gelatine printing ink, not
only on paper but also on wood, ivory, and glass, and from 1870 to
1880 stereoscopic pictures on glass were put on the market by Wilson
and others in the United States.

Woodbury sold his patent to Disderi & Co., in England, who, how-
ever, did not pay the fees; whereupon the rights reverted to him. He
founded, in 1868, the Photo Relief Printing Company, which under-
took the business of printing Woodburytypes and followed it success-
fully for years. In France, Goupil & Co., Paris, bought the process and
employed it in their works at Asnieres. Goupil’s building was badly
damaged during the Franco-German War in 1870, but was soon re-
erected. Director Rousselon continued its use until the modern re-
production processes displaced the Woodburytype.

In addition to the firm of Goupil, which later was succeeded by
Boussod and Valadon, Lemercier & Co., in Paris, used Woodbury-
types in their original form (with hydraulic presses) on a large scale.
The Paris photographer and art dealer Braun, at his works in Dornach
(Alsace), also bought the rights for the use of Woodbury’s process,
but he employed it very little in his reproduction of paintings, because
it was not as suitable as the pigment printing process, for the large sizes
required in reproductions of art subjects. This author, on a visit to
Braun’s works at Dornach, saw there the complete equipment for
printing Woodburytypes with hydraulic presses, turntables, and a
number of small printing presses using gelatine printing inks. He suc-
ceeded in acquiring the equipment for the Graphische Lehr- und
Versuchsanstalt, in Vienna, where it was installed, and for decades it
was the last of its kind for teaching this particular technique of printing.

PHOTOELECTROTYPES

589

Later, interest in this process waned, and in 1928 the Woodbury-
type press was sold as scrap iron. Thus, the last witness of a one-time
extremely valuable photomechanical reproduction method passed into
oblivion; but the educational courses in the graphic arts relating to
Woodburytype were continued.

In Belgium, until the beginning of the eighties, the Woodburytype
process dominated the photographic reproduction methods to a great
degree. For instance, on the occasion of the wedding of Crown Prince
Rudolph of Austria to the Belgian Princess Stephanie, in 1 8 8 1 , thousands
of Woodburytype portraits of the bride were sold in Austria.

For the first edition of this author’s Handbucb (1884, Vol. 1), the
Woodbury Permanent Printing Company, London, furnished an
insert for the edition of 2,000 copies from an instantaneous exposure,
then still very rare, by Marsh Brothers in England. Woodburytypes
were not used industrially to any extent in Austria and Germany,
because the demand could be satisfied by the heliotype process, which
even at that time was quite well developed.

But even in England, France, and Belgium, Woodbury’s process
disappeared entirely from the graphic field in the nineties, displaced
by heliogravure, the halftone process, Klic’s rotogravure, and intaglio
rapid-printing presses. These processes are capable of producing large
editions in a very short period of time, and require no cutting and
pasting of individual pictures on pasteboard; they permit the incor-
poration of illustrations in the text and allow the execution of large
sizes; but they have never been able to attain the soft gradations, the
superb rendering of middle tones and modulated shadows characteristic
of the Woodburytype.

PHOTOELECTROTYPES FROM PIGMENT (HARDENED) RELIEFS

A success equally as great as that of the production of the intaglio
lead plates molded by hydraulic presses was attained by Swan’s and
Woodbury’s process of photoelectrotype heliogravure for intaglio
printing on a copperplate printing press.

Schielhabel, called Mariot, 11 a photographer in Graz (Styria), recog-
nized in the earlier photoelectrotype method of Swan an excellent aid
for photographic copperplate printing. In 1867 he produced sample
plates by electrotyping pigment pictures, evidently inspired by Swan’s
and Woodbury’s inventions (already known at the time), and sent a
proof of the subject photographed from nature, as well as a reproduc-

PHOTOELECTROTYPES

590

tion of an outline drawing, to the Military Geographic Institute, Vi-
enna. The importance of this process for the production of maps was
at once recognized there, and Mariot was called to Vienna and in 1 869
began the making of maps on a large scale for the General Staff of the
army by “heliogravure,” as this photoelectrotype process was sub-
sequently named. The Austrian government was the first to put this
process into practical use for map making, and used it with the greatest
success for the unusually rapid and precise production of military maps.

The Military Geographic Institute, Vienna, played an important
role in the history of the graphic reproduction processes. It was found-
ed in 1 806 as a printing office and enlarged in 1 8 1 8 by the addition of a
lithographic department. In 1 8 39 the Military Geographic Institute at
Milan (which then belonged to Austria) was merged with it. In 1862
Baron Schonhaber introduced photography, and in 1865 photolitho-
graphs were printed there on rapid-printing presses. Mariot introduced
(1869-91) heliography and photoengraving. Heliography was made
usable for general photographic practice by Wilhelm Roese (1781-
1883). The outstanding merit for the promotion of the scientific side
of photography at this institute belongs to O. Volkmer and Lieutenant
Field Marshal Baron Hubl.

Later the photoelectrotype-heliographic process was greatly im-
proved by Roese, who was section chief at the institute, and during his
time reproductions of numerous art subjects were made for sale. Roese
was called in 1885 to the Government Printing Office at Berlin, where
he introduced this method and Klic’s process. The Austro-Hungarian
Bank employed, from 1877 to 1903, electrotypes of photographic pig-
ment reliefs for the production of banknotes, 12 but in 1903 this method
was again abandoned and the government returned to copperplate
engraving for this purpose. In the reproduction of art subjects the
method also lost ground in the same degree as heliogravure by the
etching process gained favor.

Chapter LXXXIX. production of helio-
gravures BY MEANS OF THE ASPHALTUM METH-
OD; BEGINNING OF HALFTONE STEEL ETCHING

The first attempts to etch heliogravure prints on steel were based
(with the exception of etching daguerreotype plates) on the use of
light-sensitized asphaltum as an etching top.

Niepce de Saint-Victor, the cousin of Nicephore Niepce, continued
in 1853 the experiments begun in 1814 by the latter of etching helio-
gravures on metal by the asphalt process. He was convinced that the
etching of daguerreotype plates presented too many difficulties. Niepce
de Saint-Victor joined the Parisian engraver Lemaitre, and they sub-
stituted steel plates 1 for pewter and copper, which Nicephore Niepce
used in the beginning. On May 23, 1853, Niepce de Saint- Victor pre-
sented his first dissertation on his improvement of the asphaltum proc-
ess 2 before the Academy in Paris. At first he could only reproduce
outline drawings on steel and therefore progressed really no further
than his cousin.

But in 1883 he presented to the public halftone etchings from photo-
graphs taken from nature, which unquestionably were the most beauti-
ful examples of halftone etching on metal (for intaglio printing presses)
offered at the time, showing a surprising perfection in the delicate
middle tones. Niepce de Saint- Victor’s achievement in connection with
his heliographic halftone steel etchings consisted in introducing into
photographic technique the old aquatint grain, well known to artists,
to which the delicate middle tones were due.

Niepce de Saint- Victor combined the asphalt prints on steel with
the dusting-on and melting in of powdered resin along the line of the
aquatint method. 3 This fine grain he declared to be indispensable in
making halftone pictures suitable for heliogravure printing (intaglio
plates) , which he expressly pointed out in his publication on heliogra-
vure ( 1 856) . 4 Niepce de Saint- Victor built a box in which the aquatint
grain was produced by whirling around the powdered resin blown on
by a bellows. He laid the steel plate on a shelf in the grain box, the
agitated resin dust deposited on it and was then melted in. Thus fine
halftones and good printing plates were obtained by deep etching of
the low portion of the plates.

After Niepce de Saint- Victor’s report on May 23, and another of
October 21, 1853, several persons devoted themselves at Paris to the

HALFTONE STEEL ETCHING

59 *

practical exploitation of heliogravure on steel, among whom were
especially Charles Negre 5 and Baldus. Benjamin Delessert (exhibited
at the World Fair at Paris, in 1855, reproductions of Diirer) and Rif-
faut 8 were masters of this process. The detailed description of the
method is contained in Niepce de Saint-Victor’s Traite pratique de
gravure heliographique sur acier et sur verre.

L. Cremiere, the court photographer of Napoleon III, was very suc-
cessful in the use of the steel etching method; the plates made in his
studio were printed by Sarazin.

Proofs of heliographic etchings on steel (evidently by the asphaltum
process) by Baldus, Riffaut, and Negre can be found in La Lumiere
(1854, pp. 67, 159, 167, 203; 1855, p. 67).

Charles Negre of Paris was one of the first painters to employ photog-
raphy for artistic reproduction. In January, 1854, he joined Niepce de
Saint- Victor for study and in the same year published a lovely album of
halftone pictures reproduced by the heliogravure on steel process
(asphaltum method) . 7

Baldus, about 1854, used Niepce de Saint- Victor’s asphalt method
for producing a print (from a diapositive) on copper, but he did not
etch with acid or anything like it, but in a galvanic bath. He suspended
the copperplate, on which was the print on aquatint grained asphaltum
ground, at the positive pole of a galvanic battery in a salt solution; this
caused the metal at the anode to dissolve, that is, it was etched. By
painting in the halftone portions of the plate the etching could be done
in graduated stages. A greater or lesser distance of the electrodes (curv-
ing of the cathode) was also employed to regulate the graduated
depths of the etchings. 8

Those using heliogravure later overlooked the enormously important
influence of the aquatint grain on printing on a copperplate printing
press, and even Talbot seems to have been unaware of this favorable
effect, while making his first photogravure etchings on copper; at least,
he writes nothing about it in his earliest publications on photographic
steel engraving, and, as appears in his printed proofs, he had not used
aquatint grain in the sixties. Yet this is of basic importance for good
printing of heliogravure halftone etchings.

ETCHING ON RUSTLESS STEEL

In modern times rustless steel (alloys of steel with chronium, nickel,
chromium tungsten, etc.) has been produced, which is more difficult to

PHOTOGRAVURE AND ROTOGRAVURE

593

etch than ordinary steel. Alois Schafer, for many years a photoengraver
in Vienna, succeeded in 1929 in etching such steel objects for decora-
tive purposes, using a photographic chromate etching ground. He pro-
duced portraits with delicate halftones on rustless steel, which remind
one to some degree of daguerreotypes; they offer great resistance to
atmospheric and mechanical influences and open new possibilities for
photographic steel etching.

Chapter XC. heliographic steel and cop-
per ETCHING WITH THE CHROMATED GLUE PROC-
ESS; KLIC’S PHOTOGRAVURE; PRINTING WITH THE
DOCTOR; ROTOGRAVURE

talbot’s photoetchings on steel and copper

Fox Talbot discovered the light-sensitivity of potassium bichromated
gelatine and the change of solubility (swelling) in water after ex-
posure. He drew at once the conclusion from this observation that
exposed chromated gelatine layers on metal plates must act as pro-
tecting tops against aqueous etching solutions. In 1852 he invented
the first such photoetching method by producing images with chro-
mated gelatine on steel plates, etching them with a solution of platinum
chloride, and thus obtaining an intaglio surface from which impressions
could be made on a copperplate printing press.

He took out an English patent in 1852 on this steel etching process,
and in the following year he presented to the Paris Academy of Sciences
not only his specifications but also printed specimens from his etched
steel plates ( Handbuch , 1922, IV (3), 22).

Later Talbot recognized that iron chloride furnished a better and
cheaper etching medium than platinum chloride for steel and in par-
ticular for copper. Iron chloride also offers the advantages that it
leaves the insoluble portions of the chromated gelatine prints unharmed
and that even when in greatly concentrated solutions it has a tanning
effect on the gelatine. Talbot worked out on this basis a new copper
etching process for images that gives a better rendering of the halftones.

One of the earliest proofs made by this process appeared in the
Photographic News (1858, Vol. I, No. 10), and while imperfect, it
is very interesting for the history of photogravure.

PHOTOGRAVURE AND ROTOGRAVURE

594

Still very imperfect, but greatly improved, is a photogravure, or,
as Talbot called it, “photoglyph,” made by “Talbot’s patented process”
in 1859, 1 of the Tuileries in Paris (from nature) that appears as an
insert to the Photographic News of September, 1859. This photo-
gravure shows delicate middle tones without handwork, but the printed
proofs lack strength in the shadows, because the aquatint grain is
missing.

Talbot had mastered the manipulation of the iron chloride solu-
tions of different strengths and therefore easily obtained soft grada-
tions in his etched plates, which was uncertain or impossible without
additional handwork before Talbot’s invention. The introduction by
T albot, in 1 8 5 2 , of these processes giving intaglio engravings on copper
plates with bichromated gelatine as light-sensitive etching ground, with
iron chloride in varied strength as etching fluid, opened the road for
modern photogravure.

Talbot’s outstanding merit is his invention of the bichromated gela-
tine process for the production of halftone photogravure plates not
only on steel but also on copper, and the specification of iron chloride as
the best etching medium for this purpose.

In his early publications on photoetchings Talbot mentions nothing
of a dusted-on and melted grain, but recommends that a piece of
gauze (crossed lines) be inserted between the negative and the metal
plate. This would unquestionably give Talbot the credit of being the
forerunner of the later process of photogravure with a screen for
intaglio printing plates, for this furnished the basis for the breaking
up of images by a screen into lines and dots, so important in the halftone
process and for screen photogravure printing with a “doctor.”

At the London Exposition of 1862 the earlier photoelectrotype pro-
cess of Pretsch was threatened with serious competition by Fox Tal-
bot’s intaglio photoetchings. Talbot’s photogravures, mostly landscapes
and architectural subjects, even at that early stage of his process pre-
sented soft gradations of tones and met with great success. His con-
temporaries were liberal in their appreciation of his work. “Talbot has
opened a new field for photography and the graphic arts by his helio-
gravure (halftone copper etching for gravure presses) and he has justly
earned the prize which the jury has awarded him,” writes H. W.
Vogel, one of the official reporters at the exposition. In fact, the
further progress of photogravure is directly traceable to Talbot’s in-
vention.

PHOTOGRAVURE AND ROTOGRAVURE

talbot’s successors in the practice of photogravure

595

The sale of art subjects reproduced by photogravure (intaglio en-
gravings printed on copperplate printing presses) flourished especially
in France because of the work of Lemercier, Negre, Gamier, and
other Paris photographers, as was demonstrated at the Paris Exposi-
tion of 1867.

Numerous variations of Talbot’s method of etching were employed,
especially and with great artistic success by Gamier, in Paris, who re-
ceived the Grand Prix 2 at the Paris Exposition in 1867 for an excellent
photogravure of the Palace Maintenon, and by Dujardin, also in Paris,
who independently following Garnier’s results improved the method
and published many beautiful photogravures in the seventies.

The Garnier-Dujardin etching method was complicated and difficult
to manipulate. A copper plate was grained with finely powdered resin in
a grain box and the resin melted in (aquatint grain), then it was coated
in a whirling apparatus with a thin layer of chromated gelatine and
dried. A halftone diapositive was then printed on the coated plate and
the image thus obtained (of partially insoluble gelatine) was etched
with iron chloride. This first bite furnished monotone and delicate
impressions. In order to get more contrast and improve the middle tones,
the plate was thoroughly cleaned, again grained with powdered resin,
coated with another chromated gelatine solution, and another dia-
positive was printed in exact register and etched again. For the third
bite, to intensify the shadows, a diapositive with strong contrasts was
used; when the plate was finished and printed on a copperplate printing
press, splendid photogravures, with the full range of tones, were ob-
tained. The method required long experience and the assistance of
trained engravers, which the Paris firms employed. The process was
kept secret, and the manipulation did not become known until much
later, in the nineties (Hand buck, 1922, Vol. IV, Part 3). Art prints
made by this method were produced by Goupil (later Boussod and
Valadon), of Paris, both for sale in art stores and for book illustrations.
Dr. Eugen Albert, of Munich, employed this Dujardin progressive
etching method and the platinotype process in the early eighties 3 for
the production of his art prints. Later, however, he adopted Klic’s
process and other modern methods.

All these methods, however, were surpassed by the photogravure
process invented by Karl Klic, at Vienna, in 1879, based on the pig-
ment process, by which at least equally beautiful results were obtained

596 PHOTOGRAVURE AND ROTOGRAVURE

in a simpler and more certain manner. Klic transferred a pigment image
onto a grained copperplate, developed the print in warm water (wash-
out process), and then etched with iron chloride solutions of varying
strength. The pictures thus obtained showed particular sharpness, rich
detail, and halftones. They control the art trade of modern times as
far as photographic intaglio printing is concerned.

KLIc’s METHOD OF PHOTOGRAVURE ( I 879)

The zenith of heliogravure by the etching method for beauty of re-
sults, as well as for sureness and rapidity of production, was reached
by the painter and newspaper artist Karl Klic, at Vienna, who com-
bined the pigment transfer process on grained copper plates with the
etching process, and thus outstripped his predecessors.

Klic is the creator of modem photogravure with aquatint grain on
copper plates by means of the transfer of a pigment image and etching
in iron chloride baths of various strengths, in which he etched the half-
tone picture to different graduated depths. He was also the first to in-
troduce rotogravure printing with the doctor in graphic art techniques,
for which he also used the pigment process, but without grain, for
which he substituted a copied crossline screen. Both methods were of
fundamental importance, differed essentially from Talbot’s process,
and are entirely original.

Karl Klic (as the name is spelled in Czechish) or Karl Klitsch (in
German) was born on May 31, 1841, in Arnau, a small town, pre-
dominantly German, in the district of Hohenelbe, Bohemia; he died
Nov. 14, 1926, in Hietzing, a suburb of Vienna. The spelling of his
name is specified legally in the book of vital statistics in the local
vicarage. It is there registered that to Karl Klitsch, foreman of the
paper factory, at No. 71 in Arnau, was born a son “Karl Klitsch.”
The same document testifies that his grandfather “Georg Klitsch”
served as captain in the Infantry Regiment Fiirst Reissklau. There is
no other documentary record of the spelling of the name other than
“Klitsch.” Therefore this is the official way of spelling, since the Aus-
trian military formula recognizes no other spelling of this name. It was
the father of our subject who during the awakening of Czechish nation-
alism allied himself with that movement, dropped his German connec-
tions, and accepted the Czechish spelling of his name, “Klic,” thus
disregarding the spelling of the family name by his ancestors. He
induced his son, our inventor, to follow him in this. The polyglot

PHOTOGRAVURE AND ROTOGRAVURE

597

nationalities of the Austrian Empire overlooked and accepted without
protest many of these variable spellings. With filial consistency and
a patriotic spirit the inventor Karl Klic, whose native language was
Czechish, signed all his original drawings, designs, gravures, and con-
tracts with the Government Printing Office, Vienna (1881-82), with
the name “Klic.” His gravure establishment was officially registered
under the title “Klic’s Photochemische Werkstatte, Wien IV, Belve-
deregasse 22.”

We tarry longer on the discussion of the spelling of his name, be-
cause during the latter days of the inventor a confusion arose about
this question, for which, however, Klic himself was largely the cause.
In the latter years of the last century (see below) he lived for many
years in England. English people found the Czechish pronunciation of
his name difficult and called him “Mr. Klik,” which annoyed him
greatly. This caused him to call himself in England “Klietsch,” as he
related to this author in Vienna, which he had left as “Klic” and re-
turned to as “Karl Klietsch,” director of the Rembrandt Intaglio Print-
ing Co., Ltd. This new spelling of his name was, of course, contrary
to the official records.

The new spelling was announced to this author by a visiting card.
Klic’s Vienna relatives accepted this spelling (Klietsch), while those
in Briinn declined it, since it was not according to the official docu-
ments. This erroneous spelling “Karl Klietsch” is unfortunately found
on his tombstone, at Hietzing, as well as in the otherwise excellent
biography by Professor Karl Albert, of Vienna. This spelling is, how-
ever, incorrect and was invented by Karl Klic only during a playful
mood.

This is difficult to understand without going into the meaning of
the Czechish word “Klic.” According to the Czechish grammar the
letter “i” (carrying a dot) is pronounced short, while with an accent,
“1,” it sounds soft (long). The Czechish word “Klic” in English means
“key,” which tickled our inventor’s risibility, and he often signed
himself as a key or hook. The long “i” appears in German writing as
“ie” and Klic’s sense of humor caused him to sign his name as “Klietsch,”
distorting it still more. This is accurately proved by the author in
Phot. Korr. (June and August, 1928). The historian therefore must
spell the name either according to the Czechish manner “Klic” or fol-
lowing the German “Klitsch,” but never “Klietsch.” We are bound
above all to respect the use of his Czechish name “Klic,” which he as

598 PHOTOGRAVURE AND ROTOGRAVURE

inventor of the modern rotogravure printing process, as business man,
and as artist chose during his most active period. It is this spelling of
his name by which he introduced himself internationally. [The trans-
lator was told on a visit to Mr. Klic that he insisted on the Czechish
spelling of his name.]

Karl Klic showed a great talent for drawing in his youth and he
went to Prague to study under Professor Engerth. His father moved
to Briinn (Moravia), where he started a photographic studio in which
his son had to assist him. But young Klic was more interested in draw-
ing and lithography and drew cartoons and caricatures for the news-
papers. His work attracted attention, and he was called to Budapest in
1867 as a newspaper artist. Later he went to Vienna and became a
favorite caricaturist for comic journals. He drew with so-called chemi-
cal india ink on zinc plates which were etched in photoengraving shops
in Vienna. Then he learned zinc relief etching, and from 1873-74 he
made his own line plates. During all this time he looked for a method
for better halftone reproduction by experimenting with the pigment
process and the transfer to copper plates.

He began experiments with photographic copper etching in 1875,
and had so far progressed in 1879 that he was able to apply his proc-
ess practically, exhibiting his photogravures in October of that year
at a general meeting of the Vienna Photographic Society. He made
the short announcement that his “heliogravures” (beautiful halftone
pictures on paper, printed on an ordinary copperplate printing press)
“were produced on solid copper by etching.” At the same meeting Klic
exhibited cotton cloths which had been printed by the photogravure
process from cylinders prepared by him. In November, 1880, Klic
again exhibited at the Vienna Photographic Society a collection of his
photogravure reproductions of portraits and other subjects from nature.
Other early prints of Klic’s photogravures are to be found in Tboto-
grapbiscbe Korrespondenz, at the Graphische Lehr- und Versuchs-
anstalt, and in the Technical Museum at Vienna.

Klic produced his photogravures from diapositives on coffee-collo-
dion dry plates, which he at first had made by Victor Angerer in Vi-
enna. Later, Klic made his own diapositives on tannin-collodion dry
plates, but he soon turned to the production of glass diapositives by the
pigment process.

His work soon became well known, because Klic made single gra-
vures to order, published them, and also delivered heliographic copper
plates. Since he worked either alone or with only a few trustworthy

PHOTOGRAVURE AND ROTOGRAVURE

599

men, owing to his desire to keep his manipulation a secret, his output
was small and reached only a limited circle of art lovers; beyond the
borders of his own country his process and its advantages remained
unnoticed. Klic did not apply himself very intensively, even leaving
uncompleted an order for the imperial collection. The English journals
published Klic’s invention in 1 88 1 . The editor of the Photographic
News and of the Yearbook of Photography, London, Captain Baden-
Pritchard, requested this author to order from Klic a heliogravure of
Mungo Ponton’s portrait and 2,000 impressions from it. This work
appeared as an insert to the Yearbook for 1882 with the credit line,
“Heliogravure by Klic, Vienna.” This was Klic’s debut in England,
and it made the craftsmen there acquainted with his work.

Klic had decided to leave Vienna, and he sold licenses for the rights
to his process, with the provision of secrecy, 5 to several interested
parties, one of which was the Government Printing Office, which made
a contract with him on January 1, 1881, and paid him 2,000 florins.
Others who bought the process were Jos. Lowy and Victor Angerer. 0
The clients were taught at the small “Klic Photochemical Works.”
Then Klic sold licenses for his process in Germany to Hanfstangl,
E. Albert, and Bruckmann, in Munich, Meisenbach and Riffarth, in
Berlin, Braun, in Dornach, and others. He also licensed some firms in
France and England, where he introduced his process personally.

He brought to England his process of rotary photogravure (roto-
gravure) with etched cylinders for machine printing. He remained in
England until 1899 and earned sufficient money there to be able to
retire to his own villa at Hietzing, one of Vienna’s residential suburbs.
Here he died in November, 1926.

Color photogravure (after the style of English color prints from
eighteenth century copperplate engravings), produced by tamping
colored inks on the copper plate with small printer’s balls (tampons),
was first attempted by Boussod and Valadon, of Paris, about 1 880; later
by Blechinger and Leykauf, at Vienna, about 1893, and still later by
the Government Printing Office at Vienna.

KLIC INVENTS (1890) ROTOGRAVURE PRINTING FROM CYLINDERS ON FAST
PRESSES WITH THE USE OF CROSSLINED SCREEN; USE OF THE DOCTOR
IN FINE PRINTING, AS WELL AS FOR PRINTING ON FABRICS AND WALL-
PAPER

Photogravure reached its full capacity for mass production only with
the introduction of cylinders for intaglio printing, for which, how-

6oo PHOTOGRAVURE AND ROTOGRAVURE

ever, specially constructed presses were required. Such a press for re-
productions of outline drawings, and copper and steel engravings, was
constructed in practical form in 1877 by Const. Guy, of Paris. This
press was equipped with an automatic cleaning and wiping device for
use on rotating cylinders. But this press was useless for halftone photo-
gravures.

Another idea for the rapid production of these delicate photo-
gravures from the ordinary flat copper plates, by a method similar to
lithography (lithographic rapid presses), also originated in France
( Handbuch , 1922, IV(3), 83).

At the Paris Exposition of 1889 the press-builder Marcilly exhibited
a kind of lithographic rapid-printing press for ordinary halftone photo-
gravures and printed on it some of Dujardin’s grained halftone photo-
gravure plates. Both Guy and Marcilly accomplished the mechanical
wiping of the copper plates by cloths moving in a straight line, which
resulted in uneven impressions. Laviere, in Paris, improved this press
in 1 894 by equipping it with rotating balls for wiping the flat copper
plates.

For the rapid printing of large editions the adaptation of photo-
gravure to rotary cylinder presses was of great importance. It is known
that Pretsch, then Swan, and also Woodbury had this idea in mind,
but their plans proved unsuitable for practical execution.

J. F. Sachse expressed himself most clearly in the matter of produc-
ing etched photomechanical printing cylinders by etching bichromated
gelatine prints.

Sachse, who had previously taken out several patents for textile
printing (Brit, patent No. 2,724, July 4, 1879), was granted a British
patent (No. 1,909, May 10, 1880), on a process of coating a metal
cylinder with bichromated gelatine, printing a positive on it by elec-
tric light, the cylinder being slowly turned during the exposure and
the print being subsequently etched with iron chloride. Sachse also
described the transfer of the photographic print from the bichromated
gelatine paper (pigment paper) to the cylinder, the washing out, and
the etching. He does not mention the crossline screen, nor had he been
able to use halftone images.

Klic recognized in 1 890 that for photogravure printing from rotary-
press cylinders a screen formation was more suitable than the aquatint
grain. He became acquainted with the use of the doctor 7 employed
in ordinary rotary intaglio printing at the textile print works at Neun-

PHOTOGRAVURE AND ROTOGRAVURE 601

kirchen (Lower Austria), where textiles and wallpapers were printed
( Handbuch , 1922, Vol. IV, Part 3). He grasped the great advantage
of the continuous delivery by rotary intaglio presses over that from
flat-bed presses. Klic improved on Talbot’s awkward interposition of
black nets and avoided the breaking up of the image, as practiced in
the halftone process, into lines and dots of various sizes. He printed a
positive crosslined screen with transparent lines and opaque dots on
the pigment image to be transferred on the cylinder, which resulted
in producing a delicate screen structure with raised lines on the pig-
ment gelatine top. When the doctor passed over these raised lines, it
removed the excess of printing ink from the surface of the plate and
allowed it to remain in the sunken parts of the plate, which had been
etched to varying depths and represented the picture. Klic named the
beautiful halftone intaglio impressions so obtained, “Rembrandt in-
taglio prints.”

Viewed through a magnifying glass, the Rembrandt prints (Klic
process) show white thin crossed lines, which break up the picture.
These white lines stand out from the dots, etched to varying depths,
and are found almost altogether on the surface of the copper plate.

It is on this foundation that Klic introduced his process at Lancaster,
England, where he became a partner in the Rembrandt Intaglio Print-
ing Co., which he and Samuel .Fawcett started in August, 1 895, and
which was financed by Storey Brothers. This company kept the proc-
ess secret and expanded its use extensively. Their large editions, in
1895 and later, of screen photogravures for the art trade, periodicals,
and Christmas cards attracted much attention. The process was used
not only in the arts and commerce, but also by weekly journals such
as the Illustrated. London News. Subsequently they opened a branch
in London.

ADOLF BRANDWEINER, INDEPENDENTLY OF KLIC, INVENTED INTAGLIO
PRINTING CYLINDERS WITH CROSSLINE SCREEN IMAGES AND PUB-
LISHED THIS PROCESS, IN 1 892, IN THE PHOTOGRAPHISCHE KORRE-
SPONDENZ

Adolf Brandweiner 8 made the photographic part of his experiments
at the Graphische Lehr- und Versuchsanstalt, Vienna, with asphaltum,
but employed also pigment paper transfers, used a screen in printing
on metal and a doctor for the removal of the ink from the surface of
the cylinder. He realized the importance of the raised screen lines for

602 PHOTOGRAVURE AND ROTOGRAVURE

intaglio printing with a doctor. At this time Klic’s process was kept
strictly secret, and Brandweiner could not have known anything about
it. He produced in 1891 at the Graphische Lehr- und Versuchsanstalt
steel cylinders, prepared according to his idea, for the cotton-printing
firm Cosmanos, in Josef tal (Bohemia); these cylinders are preserved
in the technical museum at Vienna. While Brandweiner probably men-
tioned the use of this process for printing on paper, he did not pursue
it in this direction. Brandweiner’s rights to priority, as far as the publi-
cation of this invention is concerned, are today fully established, and
they played a great role in later patent suits ( Handbuch , 1922, IV(3),
94; and Jabrbuch, 1906, p. 581). In fact, neither Klic nor the Rem-
brandt Company ever patented their process or initiated court proceed-
ings, but contented themselves with keeping their method secret.

Theodor Reich, a technician in the reproduction processes, born
at Vienna, in 1861, lived in 1895 in London, where he was employed.
The Rembrandt screen rotary photogravures came early to his atten-
tion, and by careful consideration of the formation of the light screen
cross lines in these photogravures, he arrived at the correct method
of producing these printing plates. Without further knowledge of
Klic’s secret manipulation, he succeeded in producing such photo-
gravure copper plates. He did not, however, print these plates on a
rotary press, but worked with flat copper plates, printed on a sort
of lithographic press, using the doctor for the removal of the super-
fluous printing ink. This allowed an increased speed in production
greater than the early Klic method with aquatint grain and the slow
wiping with pads and tampons. The method was quite adaptable for
small runs, but of course it could not compete with the large produc-
tion of rotary intaglio printing. He therefore reconstructed his litho-
graphic presses.

Reich first introduced the method invented by him in England,
where he founded the Art Photographic Company, Limited, which
he managed from 1897 to 1903.

He sold his process ( “mezzo-tin to-gravure”) in 1903 to Bruckmann,
in Munich, and introduced it in 1904 to the Wiener Kunstdruck
Aktien-Gesellschaft, 9 formerly J. Lowy, as well as in firms in France
and America. 10

The manipulation in Reich’s method is relatively simpler than rotary
printing, but the latter is much faster and later entirely displaced the
printing of flat-plate gravure plates when large editions were de-
manded.

PHOTOGRAVURE AND ROTOGRAVURE 603

PATENT DISPUTES OVER ROTARY INTAGLIO PRINTING WITH PHOTOGRAPHIC
CROSSLINE SCREEN PRINTING CYLINDERS; AWARD OF PRIORITY TO
BRANDWEINER BY THE GERMAN SUPREME COURT AND ANNULMENT
of maemecke-rolff’s PATENT

Klic’s invention was used in England on a large scale, but the mode
of procedure was never made public. Adolf Brandweiner, while having
assured to himself the claim of being the first to publish his similar
invention in detail in the technical publications, had disappeared from
the field of its practical application.

Klic became rather disturbed when other inventors, especially RolfF ,
took out English patents on the use of crossline screens for rotogravure
printing from cylinders; he questioned the ability of others for in-
dependent invention and claimed that he was being “spied upon.” He
kept his silence, however, because he felt that these patents would not
interfere with his work and that he could, when necessary, establish
his claims of prior practical use of the method. But no legal difficulties
of this sort arose.

At that same time Dr. Ernst Rolff, a German textile printer, with-
out having knowledge of Brandweiner’s publications, took up the idea
of producing cylinders for textile printing, employing the doctor, by
the photochemical process. This idea came to his mind on reading an
article referring to this problem in the program of the Industrial Society
of Mulhouse, May 18, 1898. Dr. Rolff applied for a German patent
covering this subject on June 13, 1899, under the name of his lawyer,
Dr. Maemecke, and for an English patent under his own name. The
English patent was granted on November 9, 1899 (No. 22,370).

The German Patent Office delayed issuing the patent, contesting
its originality, owing to Brandweiner’s publication. In fact, they had
before them only an incomplete extract of Brandweiner’s publication
contained in the book by Wilhelm F. Toifel, Handbuch der Chemi-
graphie (1896, 2d ed., p. 197). The examiner accepted Dr. Rolff’s
viewpoint that Brandweiner spoke of the use of a line screen, not of
a cross-line screen, and granted the patent on June 15, 1899 (No.
1 29,679) for the use of the cross-line screen in rotary intaglio printing,
which seemed to imply a kind of monopoly for the use of cross-line
screens for rotary intaglio cylinders in Germany, England and other
countries.

Dr. Eduard Mertens, chemist and technician in the graphic arts, who
worked along the same lines quite independently of Rolff, saw that

604 PHOTOGRAVURE AND ROTOGRAVURE

RolfPs patent stood in his way and therefore joined him, so that both
might improve their work.

Dr. Mertens had started an attack on Rolff’s patent, but the suit was
dropped on the basis of the joint exploitation of the patent. For several
years it seemed that the patent was incontestable, but events took a
different course; for the earlier claims of Brandweiner to the inven-
tion were much more comprehensive than was assumed, because of
the lack of familiarity with the original publication of Brandweiner
(Phot. Korr., 1892, p. 1).

The publishing house F. Bruckmann A.-G., Munich, and the firm
Meisenbach, Riffarth & Co., Berlin-Schoneberg, brought suit before
the Patent Office at Berlin for annullment of the Maemecke (Rolff)
patent (No. 129,679 of June 15, 1899) on the ground of several pre-
vious publications. With its decision of March 4, 1909, the Patent Office
acquiesced in the petition and annulled the patent.

Ernst Rolff appealed this decision to the Supreme Court; the joint
owner of the patent, Dr. Mertens, did not participate in the appeal.
At the session of November 26, 1910, the court confirmed the decision
of the Patent Office, and the contested patent was definitely annulled.

In this judgment the publication of Brandweiner in the Photo-
graphische Korrespondenz (1892, p. 1) played a decisive part, and
the very exhaustive opinion of the court definitely established the
priority claim of Brandweiner to the invention, which had been con-
ceded for a considerable time previously in technical circles.

The reasons upon which the court based its judgment, in its thorough
objectivity, are of such interest for the history of rotary intaglio print-
ing that the author printed them in his Handbuch (1922, IV (3), 105).

It follows primarily from the consideration of the contents of Brand-
weiner’s article in the Photographische Korrespondenz (1892, p. 1). . .
It was in no way Brandweiner’s opinion that the intaglio cylinder for
photomechanical textile printing required a single-line screen. On the con-
trary, he advocated for this purpose the underlying idea, which is claimed
as the essence of the Maemecke-RolfF patent, namely, the application of a
cross-line screen. This follows without question from the original publi-
cation, where it is clearly stated that the halftones must be broken up into
lines or dots; but cannot be formed with a single-line screen. It further
follows from the fact testified to by Dr. Aliethe that the use of the single-
line screen had been entirely abandoned before 1902 and that every ex-
pert employed the term “screen” as meaning “cross-line screen” unless
otherwise specified.

PHOTOGRAVURE AND ROTOGRAVURE 605

The system of crossed lines which stand out in relief on the surface of
the plate and over which the doctor passes thus had been described by
Brandweiner. . . . However, in this case it must be considered that the
particular adaptability of the cross-line screen as the surface for the attack
of the doctor had already been known. It is not only the last-cited British
patent, No. 1,791, by Swan, in 1865, which goes into this matter in great
detail. As has been explained by the expert, a cross-line screen was also
used by textile printers in the sixties and seventies of the last century.
Those earlier printers, who engraved with the roulette, used, of course,
copper printing cylinders. On the other hand, Swan’s description, while
it refers to flat-bed printing, takes the photomechanical screen as a basis.
But the idea that a cross-line screen was pre-eminently suitable for the use
of the doctor was common property in the industry.

Under these circumstances it may appear strange that a cylinder pre-
pared photomechanically with a cross-line screen, was not used, as far as
we know, for intaglio printing before the contested patent was taken out.
One may speculate as to the reasons which might give an explanation for
this, but this cannot alter the decision. The patent is declared null and
void, not on account of prior use, but on account of prior publication.
This cannot be denied in the face of Brandweiner’s article when properly
interpreted. . . . RolfPs appeal is denied.

This exhaustive argument of the court unquestionably proves that
Adolf Brandweiner was the first, in 1892, independently to invent
rotary intaglio printing (rotogravure) with a crossline screen and
doctor and to make this process public. This decision by the highest
court removed the threatened monopoly in the manufacture of photo-
mechanical intaglio printing cylinders with a screen.

INTRODUCTION OF ROTARY INTAGLIO PRINTING (ROTOGRAVURE)

FOR NEWSPAPERS BY EDUARD MERTENS

Dr. Eduard Mertens (1860-1919), studied chemistry and physics
at Berlin, Kiel, and Geneva and received his doctor’s degree in phi-
losophy at Berlin in 1 888. About the same time as Rolff he investigated,
independently and alone, the same problem of photomechanical print-
ing with the use of a doctor. He started a concern for engraving and
printing near Berlin in 1889, and published elaborate museum cata-
logues. In 1897 he merged a rotary gravure business with his own
establishment and commenced experiments with rotary photogravure
along the lines of Klic’s method (which the latter used in England
as a secret) under the name “Graphische Gesellschaft in Berlin von
Dr. E. Mertens & Co.”

606 PHOTOGRAVURE AND ROTOGRAVURE

In 1900 Dr. Martin Schopff joined Mertens, and between 1903
and 1905 they transferred screen images from gelatine-bichromated
paper (pigment paper) to cylinders with great success. Mertens’s per-
sonal desire, however, held fast to the use of direct photographic print-
ing on a cylinder, coated with a bichromated glue solution. In 1902
Mertens etched a halftone diapositive of the Emperor’s portrait on
the seamless cylinder of a rotary press at a wallpaper factory, and in
1903 and 1904 he contracted for the construction and delivery of
rotary intaglio printing presses. The Alsace Printing Machinery Co.,
Miilhausen, exhibited in Mertens’s laboratory in 1904 a special roto-
gravure press for illustrations and text, with three thousand revolutions
per hour.

Dr. Mertens’s achievement lies in the ingenious construction of the
mechanical parts of the rotary gravure press, by which it was made
possible for newspaper presses to print gravure plates at a high speed,
thus paralleling the slower gravure presses for finer grades of illustra-
tions as Klic used them.

In 1904 Mertens elaborated his combination of typographic and
gravure printing in one printing operation for newspapers. The first
attempt of newspaper gravure printing, in which halftone pictures
and text were delivered from on d 1 he same printing cylinder, was
produced by Dr. Mertens in part of the newspaper Der Tag of April
26, 1904. The author, who has seen this copy, must pronounce it
perfectly successful. Dr. Mertens was the first to print illustrated
papers and newspapers on fast gravure printing presses, and without
doubt we are indebted to him for rotary gravure printing at high speed.

The Mertens’s German company, in Freiburg (Deutsche Mertensge-
sellschaft), which he founded, worked in the whole field of book and
newspaper printing. The so-called Mertens process consisted of a com-
bination of rotary intaglio ond typographical cylinder printing presses.
The first of these tandem presses was erected at Freiburg in 1910, for
which the Alsace Printing Machinery Company delivered the gravure
presses, and Voigtlander, the typographic rotary press. The publisher
of the Freiburger Zeitung, Max Ortmann, and later the firm of Schmidt
Brothers, participated in the production of rapidly drying printing
ink.

On April 1, 1910, appeared on Easter the first number of the Frei-
burger Zeitung printed in a combination of typography and gravure
at the rate of ten thousand impressions per hour. This was the first time

PHOTOGRAVURE AND ROTOGRAVURE 607

a large illustrated newspaper was produced in such a large edition. The
illustrations were etched by photogravure, using a screen on a cylinder,
and the text was set up in the usual typographic manner; the printing
was done on a cylinder press and a rotogravure press coupled together
in tandem. This newspaper edition, which is historically so original
and important as the first printing of rotary photogravure on ordinary
cheap newspaper stock, also contained a description of the process.
The costly and complicated installation of the tandem typographic
and gravure cylinder presses forced illustrated newspaper plants to
replace the Mertens combination printing method with the printing
of both text and illustrations from one and the same cylinder.

Rotary gravure printing has certain advantages over halftone re-
lief printing, which rest in particular on the possibility of using inferior
uncoated paper. The method of preparing printing cylinders with half-
tone screen formations, using the doctor and carbon tissue, as well as
the transfer of the pigment images onto the cylinder, corresponds
completely to the early Klic “intaglio process,” which originally had
been kept a strict secret. Although for a long time this fact seemed
wrapt in mystery, the historical truth eventually came into its own
( Handbucb , 1922, Vol. IV, Part 3).

USE OF GELATINE SILVER BROMIDE PAPER IN PLACE OF PIGMENT PAPER
FOR THE TRANSFER OF IMAGES SUITABLE FOR ETCHING TO COPPER
PLATES

Silver bromide papers, which can be printed much more rapidly,
can be used for photogravure in place of pigment paper if the image
is prepared according to Warnerke’s process or along the lines of bro-
moil prints. In this manner resist transfers on copper can be produced
which are suitable for photogravure etching with iron chloride.

In 1891 Oskar Pustet, of Salzburg, described his experiments with
a photographic etching method, in which he was the first to use War-
nerke’s transfer method for a gelatine silver bromide image, developed
with pyrogallol after the manner of pigment printing, on copper and
etched grained photogravures ( Jahrbuch , 1891, p. 195). Then War-
nerke himself mentioned this method of “photogravure” (Jahrbuch,
1899, p. 587). This is the procedure given for the use of the gelatine
silver bromide images, tanned in the silver portions of the picture by
suitable developers. While Pustet and Warnerke developed with pyro-
gallol, Gustav Koppmann later used the alkaline developer pyro-

6o8

PHOTOLITHOGRAPHY

catechin, which acts similarly, for the transfer of gelatine silver bromide
images to copper plates (after the manner of carbon prints) for photo-
graphic etching. But this method was never employed in photographic
practice.

The bromoil process also starts with gelatine silver bromide paper,
because the developed silver bromide images are tanned in their silver
parts in a bath of bichromate and potassium ferricyanide or copper
bromide. These layers can then be etched along the lines of photo-
gravure, or they can be transferred to copper plates by the carbon
printing method and etched in combination with crossline screens.
This method of screen photogravure was published in April, 1914, by
Paul Schrott, who took out an Austrian patent (No. 72,450) and a
German patent (No. 303,136). The practicability of this method
Schrott 11 demonstrated by a screen photogravure, which he produced
at the Graphische Lehr- und Versuchsanstalt, Vienna, and which ap-
peared in 1918 in the Photographiscbe Korrespondenz (1918, No. 695;
see also Handbucb, 1922, IV(3), 134).

Thus the historical development of the application of gelatine silver
bromides, which can be printed so fast and are so adaptable to the
direct enlargement or reduction of pictures for photolithography and
collotype, had also come to photographic copper printing; of course,
for the latter purpose gelatine silver bromide could not take the place
of the earlier method with pigment paper in practice.

Chapter XCI. photolithography; zincog-
raphy; ALGRAPHY

We shall leave out of consideration the fact that in his experiments
with light-sensitive resins in 1815 and 1816 Nicephore Niepce used
lithographic stones. While he thus attempted photolithography, he
attained no practical results and dropped the method in favor of what
he called “heliographic etching on metal. It is, therefore, difficult to
justify the claim sometimes made, that he should be called the inventor
of photolithography. It is true, however, that long after Niepce’s
death the starting point for the production of photolithographs was the
heliographic asphaltum process invented by him.

The first successful attempts to produce halftone photolithographs
by the asphaltum process were made by Lemercier, Lerebours, Barres-

PHOTOLITHOGRAPHY 609

wil and Davanne in Paris, who published the first experiments in 1852.
Lemercier was a famous Paris lithographer, and Lerebours the well-
known photographic optician in Paris; the other two were chemists
and amateur photographers. The right kind of men had associated
themselves for joint work, and they soon produced fine photolitho-
graphs. They coated grained lithographic stones with asphaltum, ex-
posed under a paper negative, washed with turpentine, and obtained
photolithographs 1 ready for printing by the ordinary method on litho-
graphic presses.

They published a now very rare collection 2 of these direct asphalt
photolithographs in 1853, entitled Lithophotograpbie; ou, Impressions
obtenues sur pierre a I'aide de la photographie, by M. M. Lemercier,
Lerebours, Barreswil and Davanne. The first number contained photo-
lithographs, size 40 X 57 cm. (about 15%" X 22 %"), showing archi-
tectural subjects of Strassburg (negatives 1851), of Chartres (nega-
tives 1852), Neuviller, Beauvais, and other places. This publication,
which has entirely disappeared from art and book stores, is the earliest
portfolio of photolithographs in the halftone manner. These asphaltum
“lithophotographs” show remarkable strength, with a somewhat coarse
grain in the middle tones. We must consider them the first successful
attempts at printing on lithographic presses halftone photographs
copied directly on stone.

The uncertain manipulation and the washing of the large stones with
turpentine, which was rather expensive at that time, were a hindrance
to the spread of the method, but it was reintroduced later with great
success by other photographers.

Poitevin’s invention of the bichromated albumen process on stone,
however, soon relegated the asphaltum process to the background,
because Poitevin’s method was more certain, required a shorter ex-
posure, and needed only water for washing, advantages which soon
attracted attention.

In the early months of 1855 Poitevin discovered the property that
mixtures of potassium bichromate with gelatine, albumen, gum arabic,
and other substances, after exposure to light have of retaining greasy
printer’s ink, while rejecting water in the exposed parts, the unexposed
parts retaining their solubility or ability to swell in water. Poitevin,
with great vision, at once recognized the far-reaching importance of
his observation and thus invented the principle underlying collotype,
photolithography with chromate layers, as well as pigment printing.

6io

PHOTOLITHOGRAPHY

The first practical application of a potassium bichromated gum mix-
ture for direct prints on stone for the production of photolithographs
is supposed to have been made, according to several statements, by the
American Joseph Dixon (1841), in Massachusetts (Harrison, History
of Photography , 1888, p. 99); but the first published account of the
process did not appear until 1854, in the Scientific American , and did
not become known or adopted in practice.

Poitevin patented his process in August, 1855, in France and other
countries, 3 and then devoted himself entirely to the perfecting of
photolithography and the halftone process on grained stone. In order
to exploit his process, he sold all his patents for 20,000 francs in October,
18^7, to the well-known Paris lithographer Lemercier, in whose litho-
graphic plant subsequently many photolithographs in line as well as in
halftone from photographs made from nature were produced.

Poitevin coated the stone (grained for halftone pictures) with a
solution of potassium bichromate and albumen, equalized the coating
with a tampon, dried, exposed under a negative, washed with water,
rolled up with greasy ink (or rolled up first and then washed), which
only adhered to the parts which had become insoluble by exposure
to light, but did not adhere to the moist parts. The stone was then
etched and printed by the usual lithographic method.

Fine photolithographs were thus obtained; the halftone pictures on
grained stones were beautiful, so delicate in the middle tones and deep
in the shadows that even modern craftsmen are surprised by the ex-
cellence of these photolithographs of Poitevin, printed by Lemercier,
which have now become so rare. Lemercier is said to have printed
seven hundred impressions from such a photolithographic stone before
witnesses.

Ernst Conduche expressed the theoretical view that in the practice
of Poitevin’s process the stones are soon worn out by the mechanical
wear and tear on the bichromated albumen picture-images and that
photolithographs have the proper resistance in printing only when
the lithographic or greasy soap comes in direct contact with the litho-
graphic stone ; 4 he advanced practical recommendations along these
lines.

Lemercier seems to have made his largest photolithographic publi-
cations only with Poitevin’s chromated albumen method. Numerous
photolithographic halftone pictures still exist from the fifties, signed
“mise sur pierre par Lemercier (procede Poitevin).”

PHOTOLITHOGRAPHY

6 1 1

Lemercier exhibited before the Paris Photographic Society, July 20,
i860, as a novelty photolithogrnphs which had been printed from two
stones (halftone and keyplate) .

Poitevin, in his Traite de Fimpression photograpbique (1862, p. 79),
cites numerous publications by Lemercier, produced by Poitevin’s
process on grained stones. At the Paris Exposition in 1862 Lemercier
exhibited photolithographs made by both the asphaltum process and
the chromated albumen method of Poitevin.

Niepce de Saint-Victor also produced a sort of intaglio design for
ornaments by engraving on lithographic stones by the asphaltum pro-
cess, to be printed on a lithographic press ( Compt . rend., 1856, XLIII,
874, 912; Kreutzer, Jahresbericht, 1856, p. 120).

In 1855-56 Macpherson also recognized and published the impor-
tance of grained stones in asphalt-photolithography. This method was
later improved and used commercially, especially by Karl von Gies-
sendorf, at Vienna, who devoted himself exhaustively to Lemercier’s
asphaltum process. Giessendorf was employed in the Government
Printing Office, Vienna, at the end of the fifties, but found himself
with time on his hands. He improved the method of making asphaltum
prints on grained stone by the halftone method in the early sixties
and introduced the process in the lithographic plant of Reiffenstein
and Rosch, Vienna, and in 1864 he showed such prints at the Vienna
Photographic Exhibition. After the death of Giessendorf, in 1866,
Reiffenstein 5 far excelled his teacher, but notwithstanding its excel-
lence his work (in which he was later joined by L. Schrank, editor
of the Photogr aphis cbe Korrespondenz) was not appreciated at the
time and gradually disappeared; even Reiffenstein’s photolithographic
color prints, made by this method in 1 866, were produced only for
a short period.

This is historically noteworthy, because this method was the basis
for the later “Orell-Fiissli process,” which also employed color photo-
lithographic printing according to the halftone asphaltum process (al-
though with much handwork by the artist), a method by which enor-
mous editions (especially of town views) were distributed.

A direct reproduction method on grained stone with gum arabic,
sugar, and potassium bichromate was brought out by J. A. Cutting
and L. H. Bradford in Boston, 1858.® They printed from a diapositive,
directly on the stone coated with bichromated gum arabic; washed
in soapsuds, which removed the unexposed gum arabic and made the

612 photolithography

stone capable of absorbing the greasy ink on these parts; then the
exposed gum arabic was washed off with hot water, and the positive
image produced by the action of the soapsuds was printed on a litho-
graphic press. Snelling’s Photographic and Fine Art Journal (1858,
pp. 1 17, 254, 289, 321) has good examples of this remarkable method,
which, however, was soon forgotten.

For the invention of zincography with chromated albumen or gum
arabic by A. and L. Lumiere, of Lyon (1892), which produces a posi-
tive print from a positive, see Handbuch (1922, IV (3), 11). Here
must also be mentioned the light-tracing method from zinc prints (see
also Karl Albert’s Lexikon der graphischen Techniken, 1927).

The photolithographic transfer process from chromated papers was
invented by Eduard Isaak Asser (1809-94), i n 1 85 7, at Amsterdam.
Asser studied law and received his doctorate in law in 1832. He be-
came interested in Daguerre’s process, went to Paris to purchase photo-
graphic apparatus, experimented with Niepce de Saint-Victor’s photo-
graphic asphaltum process, and was familar with Poitevin’s chromated
albumen printing method on stone. He was the first to make photo-
graphic prints with greasy ink on paper coated with starch paste and
sensitized with bichromate for transfer on stone, proofs of which he
sent in 1859 to the Paris Photographic Society. Later he exhibited his
improved process at Paris, Vienna, and Amsterdam and received nu-
merous medals. 7

Shortly after Asser, J. W. Osborne, of the Survey Office of Vic-
toria, at Melbourne, reported to the Philosophic Society of Victoria
(Australia) that photolithographs could easily be produced with
photolithographic transfer papers, which are coated with bichromated
gelatine, albumen, gum arabic, or asphaltum, and on which a greasy
color print is produced. He recommended especially albumen paper,
coated with potassium bichromate and gelatine, dried, printed, rolled
up with greasy lithographic transfer ink and developed with a wet
sponge. Osborne received one thousand pounds sterling from the
government of the State of Victoria, because his process was of great
value for the production of maps. Osborne considered this process,
which he improved in 1863, novel, but mentioned that Asser also had
invented a transfer method. Osborne’s method, however, was taken
up more intensively for practical use, especially since he made trans-
fers, in i860, on zinc plates, which had been given a slight bite or
which were grained with sand.

PHOTOLITHOGRAPHY

6i 3

A. Wood called attention to the fact, in 1863 (Phot. News, 1863,
p . 154), that i t i s not necessary t o treat the greasy photographic image
on chromated gelatine with hot water, but that it suffices to place the
exposed paper rolled up with greasy ink in cold water and wipe it
with a sponge, which removes the greasy ink in the white parts, while
the parts representing the picture hold the lithographic transfer ink.

Photolithography was soon extensively employed, particularly for
the reproduction of plans, maps, and outline drawings, in conjunction
with printing on rapid lithographic printing presses, this method de-
veloped one of the lowest priced branches of lithography suitable for
mass production in the lithography trade. We cannot enter here into
further details and improvements of the photolithographic transfer
process; but we must mention that frequently halftone images were
transferred— for instance, from collotype plates or from grain paper
to smooth lithographic stones. This was proposed in 1 897 by August
Albert, of Vienna, who transferred a collotype from a smooth photo-
lithographic gelatine paper to a grained lithographic stone. For a de-
scription of these various methods refer to August Albert’s V erschie-
dene Reproduktionsverfahren mittels lithographischen und typo-
graphischen Druckes (1899).

Experiments were also made to print a worm-like grain (collotype
grain) photographically on stone, for instance, by E. Mariot, of the
Military Geographic Institute, Vienna. He made a photographic en-
largement six times the size of a natural grain collotype plate, trans-
ferred the enlargement onto a smooth lithographic stone, composed
several such pieces on a large sheet, and again printed the composite
image on stone. From this a film negative was made, used as a screen
between a continuous tone negative and photographic chromate gela-
tine transfer paper. Or he placed the grain negative in contact with
the continuous tone negative and made a diapositive (Phot. Korr., 1 884,
P- 3 )-

The impetus for direct photolithographic transfers from negatives
on glass to lithographic stones was given by engineer Carl Aubel in
1875. So-called Aubel prints were produced by coating a collodion
negative with chromated gelatine, drying it and exposing it through
the glass, then the print was washed like a collotype plate, dried,
dampened, and inked and either printed directly or transferred to
paper and printed from stone. The German firm of Aubel & Kaiser
used this method for a number of years. Fine line reproductions were

PHOTOLITHOGRAPHY

614

produced with great precision, and the photographic journals of that
period contain good proofs made by this method.

G. Pizzighelli made prints directly from gelatine silver bromide
plates with greasy ink at Vienna, in 1 88 1, and he published his process
with proofs in the Pbotograpbiscbe Korrespondenz (1881, No. 214).

A gelatine silver bromide negative, after having been developed with
oxalate of iron, fixing, washing, and drying, was bathed in a potassium
bichromate solution, dried, and exposed through the glass, as in the
Aubel method. The black lines in the negative prevented the light
from penetrating, and these parts took on water when the greasy
transfer ink was rolled on, so that the printing ink was retained only
on the transparent parts of the negative. This greasy picture could be
printed directly or transferred to a lithographic stone. Pizzighelli re-
ports in his article all the details of the procedure for this method,
which reproduce the image in its original size, while transfer papers
dampened with water will shrink or stretch and thus alter the original
dimensions.

PLANOGRAPHIC PRINTING FROM ZINC; PHOTOZINCOGRAPHY

To Sir Henry James and J. W. Osborne we are indebted for the
introduction of photo-planographic printing 8 from zinc plates, so called
“zincography,” by which impressions are produced analogous to those
obtained by printing from a stone on a lithographic press. The English
Colonel Henry James made the first successful attempts, at South-
ampton, in 1859, to transfer a greasy ink print produced on chromated
gelatine or gum to zinc, 8 which he mentions 10 in the preface which
he wrote for A. C. Scott’s Photozincography (1862).

James copied for Mr. Gladstone some old manuscripts and docu-
ments, and in 1859 he inserted in his annual report the reproduction of
a small document of the time of Edward I, which he followed with
other works. About this time James learned that Osborne had applied
for a patent on his process of photolithography. He convinced himself
that the principle was the same as that of his photozincography, of
which he had stated in his report that the method could be applied to
zinc or stone. Since James had made his report public in print and since
this report had been widely distributed among English engineers and
officials, James must be credited with being the first to publish photo-
zincography by transfer.

In September, 1861, James delivered a lecture on photozincography

PHOTOLITHOGRAPHY

615

before the British Association. 11 A gum arabic bichromate print made
on paper with greasy ink was transferred to zinc (or stone), etched
with gum arabic solution and phosphoric acid. This method was then
in use at the Ordnance Survey at Southampton.

The English Cartographic Institute, through James, produced suc-
cessfully many old and valuable manuscripts by photozincography.
Captain Scott, in his book on photozincography mentioned above,
says that in 1 862 gum arabic was no longer employed in this method
and that gelatinated paper had taken its place for the transfer of the
greasy ink pictures. The method was quite similar to that of Osborne.
Scott also mentions that one or more impressions of these greasy ink
pictures could be made on another piece of paper by placing them in
contact on a press. This was probably one of the starting points of the
later “oil print.”

About 1865 Colonel Sir James introduced planographic printing
from photographic zinc plates, besides photolithography, at South-
ampton and in the New Zealand Survey Office and later also in the
Government Survey Office at Calcutta.

James’s photozinc prints were splendidly represented at the Paris
Exposition of 1 867 by reproductions of national manuscripts, a fac-
simile of an old Shakespeare manuscript, a survey of Jerusalem, and
other reproductions.

Planographic printing from zinc displaced the use of litho stones
more and more in the whole field of lithography, especially in photo-
graphic printing, the stones being difficult to obtain in large sizes. In
printing light tracings, also, zinc was largely used.

The ease with which thin zinc plates can be curved around the
cylinder of a rotary printing press opened the way for the rapid
printing of large editions.

USE OF ALUMINUM PLATES FOR LITHOGRAPHIC PRINTING (ALGRAPHY)

When advancing engineering skill made possible the production
of thin aluminum sheets, it turned the thoughts of reproduction tech-
nicians to their use analogous to that of zinc plates. John Mullay and
Lothrop L. Bullock, of New York, wrote in 1891 that they had found
a method in which pure aluminum sheets served as substitutes for the
lithographic stone and that this metal is treated in the same manner as
the stone. 12 But in practice no one succeeded in printing from alumi-
num when the ordinary etching fluids applied in lithography were used.

6i6

PHOTOLITHOGRAPHY

The correct treatment of aluminum for printing was invented first
by Joseph Scholz, at Frankfurt a. M., who was granted a patent
September 1 8, 1892 (No. 72,478), on his “Verfahren der Zubereitung
von Aluminiumplatten.” He correctly states in the introduction to his
patent application:

Up to this time it has not been possible to prepare aluminum plates in a
suitable manner for lithographic printing. All attempts were frustrated by
the use of the etching fluid ordinarily applied to stone. This mordant did
not achieve the desired result, because it could not create a sufficiently ad-
hesive layer on the bare metal which would prevent the spread of the
printing ink.

Scholz etched with phosphoric acid, hydrofluoric acid, fluosilic acid,
etc. The method of printing from aluminum sheets, so-called “al-
graphy,” was quite successful, 13 both with and without the use of
photography, but it did not entirely displace zincography.

OFFSET PRINTING, OR INDIRECT PRINTING, FROM RUBBER BLANKETS

In offset printing, or indirect printing, the image produced by the
relief, planographic, or intaglio process is transferred from the printer’s
form to a printing cylinder covered with sheet rubber and from this
the impression is printed onto the paper. The rubber blanket, imprinted
with the greasy ink impression of the image which it is to transfer,
makes perfect contact with rough and grained paper, and large editions
are rapidly delivered by rotary presses. Since the offset process lends
itself very successfully to multicolor printing, it has found wide ap-
plication in this field. Being concerned with the history of photography
only, we cannot enter into details of the many applications of this
process.

ETCHING ON GLASS AND HYALOGRAPHY

The method of engraving based on the etching of glass with hydro-
fluoric acid through a wax coating was invented in 1670, by Heinrich
Schwanckhardt, a glass cutter of Nuremberg. Glass is coated with wax
or a similar etching ground, the design engraved with a graver (burin)
and etched with aqueous or gaseous hydrofluoric acid, as described
by Professor Lichtenberg in 1788 (Guttle, Die Kunst in Kupfer zu
stechen, 1795, p. 337). The first to produce printing plates for typo-
graphic or copperplate presses by etching on glass was probably Hann,
at Warsaw (1829), who called his process “hyalotype,” 14 Professor

COLLOTYPE

617

Bottger, of Frankfurt a. M., and Dr. Bromeis, of Hanau a. N. (1844),
as well as C. Piil, at Vienna, improved “hyalography” (1853), all of
which is detailed in Handbucb (1922, IV (3), 318).

Of special importance was the use of the lithographic transfer proc-
ess for the etching of ornaments on flat glass sheets with hydrofluoric
acid or sodium fluoride. The first technically complete description we
owe to Karl Kampmann (1889), 15 who by the addition of soft gum
elemi to the greasy lithographic transfer ink increased the resistance
of the picture transferred on the glass to the etching fluid. Kampmann
also brought photolithography to the service of this process. With
aqueous hydrofluoric acid he etched the glass for depth, retaining a
smooth and clear surface, whereas hydrofluoric acid more or less neu-
tralized with soda produces a finer or coarser mat surface. By the use
of flashed glass beautiful results can be obtained which find extensive
industrial application. Details of this method are described in Karl
Kampmann’s Die Dekorierung des Flacbglases durch Atzen und
Anwendung chemigrapbischer Reproduktionsverfabren fiir diesen
Zweck, Halle a. S., 1889.

Chapter XCII. collotype

The idea underlying “collotype” we find described as early as 1855
by Poitevin. He recognized that a plate coated with bichromated gela-
tine, after exposure to light under a negative and after being rolled
up with water, is capable of accepting greasy ink only on the exposed
parts, which makes it possible then to produce direct prints from the
gelatine coating. It took a relatively long time, however, before this
process was introduced into practical printing. Photolithography,
zincotypy, and photogravure were all used on a practical scale before
collotype or printing direct from chromated gelatine was practiced.

It was not until 1865 that the Frenchmen C. M. Tessie du Motay
and Ch. Raph. Marechal, in Metz (Lorraine), employed chromated
gelatine coatings on a copperplate base under the name “phototype,”
and at that only temporarily, because the gelatine top on the copper
base did not adhere sufficiently for printing large editions and peeled
off quickly. At any rate, they produced collotypes of good quality
in small editions for their own use, as samples for their painted glass,
and very few of these prints were known to the public. 1 These first

6 1 8

COLLOTYPE

practical collotypes, or “photo-gelatine” prints, suffered chiefly in
the reproduction of the middle tones, and these incunabula of collo-
types therefore show hard half tones, but they must nevertheless be
considered quite respectable achievements.

Collotype 2 did not become a practical and productive process until
Josef Albert, a photographer of Munich (1825-86), contributed his
important improvements. He employed plate glass as the base for the
chromated gelatine and attained the adhesion of the gelatine top by
preparing the glass with an original gelatine chromate layer that had
been exposed to light. Josef Albert aroused the interest of the whole
craft by the exhibition of his prints at the Third German Photographic
Exposition, in Hamburg, 1868. They were generally called “Alberto-
types.”

Josef Albert, the son of an engineer at Munich, studied at the Poly-
technikum, Munich. He learned the daguerreotype process and opened
a photographic studio. There he produced (about 1 869) large photo-
graphic reproductions of paintings for the art trade, and in the middle
of the sixties turned his whole attention to the photomechanical proc-
ess, which led him to the improvement of collotype. His efforts
found favor at the Royal Bavarian Court, and he was rewarded with
orders and numerous prizes at exhibitions. He was also the first to
carry out successfully practical three-color collotype. His wife con-
tinued the business after his death. His son Eugen Albert devoted
himself primarily to photogravure and the three-color halftone process,
and he introduced orthochromatic collodion emulsion into the repro-
ductive process.

A drawing teacher in Prague, Czechoslovakia, Professor Jakob
Husnik played an important part in the practical development of col-
lotype, for he achieved, as early as 1868, such noteworthy success in
publishing art subjects by this method that Josef Albert found him-
self compelled to buy Husnik’s process and incorporate its advantages
with his own.

Jakob Husnik (1839-1916) was born near Pilsen (Czechoslovakia),
studied at the academy for painters in Antwerp, became professor of
drawing in his native town and later in Prague. In the seventies the
director of the Government Printing Office invited him to continue
his experiments on collotype at the department’s plant and to improve
photozincotype, photographic etchings on copper, photogravure, and
so forth. Husnik accepted the invitation and published his results in

COLLOTYPE

619

several books. 3 He was also the founder and the expert advisor of a
company in Prague which dealt mostly in halftone engravings. After
having been pensioned, in 1889, he became a partner in the firm of
Husnik and Hausler in Prague (Phot. Korr., 1916, pp. 141, 170).

About the end of 1868 Max Gemoser, a lithographer at Munich,
introduced collotype on lithographic stone as base and called the
process “photolithography.” He joined (i860) the firm of Ohm and
Grossmann, at Berlin, in order to exploit the process in business, and
designated the process then as “Lichtdruck,” which name became
generally adopted in the German-speaking countries. Gemoser as-
serted that he was the inventor of collotype, but Josef Albert estab-
lished his claim to priority successfully. 4

In the beginning Josef Albert did his printing entirely by hand,
and his collotypes in the larger sizes were artistically executed and
made the process popular. The production of collotype prints on hand
presses was too slow for large editions; Josef Albert conceived the idea
of employing rapid-printing presses and took as his model the rotary
lithographic processes which were then in use. He ordered from Faber
& Co. (later Faber & Schleicher, in Offenbach on the Main), according
to his specifications, the first rotary collotype press, which was in
operation in 1873 and made collotype possible in large editions.

J. Lowv introduced collotype, in Vienna, in 1872, and erected the
first rotary collotype press in 1881 . B He was followed by the collotype
establishment of Max Jaffe, Vienna.

Ernest Edwards seems to have been the first to practice collotype
printing from several plates and in more than one color, a process
which he patented in England, December 8, 1869 (No. 3,543). He also
added alum to the printing top in order to harden it and took out
another patent, later, on color collotype.

Woodburytypes were gradually displaced by collotypes; in neither
method can the picture be incorporated in the text, but must be printed
seperately from the type. The advantage of collotype consists in the
possibility of printing it on paper with any desired amount of margin,
while Woodburytypes had to be “bled” and mounted to give them the
margins required. This made collotype more suitable for book illus-
tration. The method was faster and replaced Woodburytypes entirely
at the end of the nineteenth 0 nn ,; " . The use of collotype for typo-
graphic printing met with little success. 11

The best history of the collotype process is found in August Albert,

620

COLLOTYPE

Die verschiedenen Method en des Lichtdruckes (1900), from which
the short outline given above is taken.

August Albert (1854-1932) was born at Vienna, studied drawing
and painting at the academy, and devoted himself to the technique of
printing and reproduction. He did practical work in different estab-
lishments in his own country and in foreign countries, and invented,
in 1888, a photolithographic transfer paper, still in use and known to
the trade as “Albert’s Autotypie-Hochglanzpapier.” In 1877 Albert
undertook the management of the department for collotype, photo-
lithography and line etching for the firm Max Jaffc, Vienna, and in
1 890 became the technical director of the firm of J. Lowy of the same
city. In 1894 he was called to the Graphische Lehr- und Versuchsan-
stalt as professor, where he introduced collotype in colors. He was
made section chief and later government councillor and retired in
1922. He also introduced other new processes, such as a combination
of color collotype with photogravure (Phot. Korr., 1900, p. 564),
typographic collotype ( Typogr . Jahrbiicher, 1906, No. 10, p. 75),
printable pencil drawings on aluminum (Das Aluminium in seiner Ver-
wendung fiir den Flachdruck, 1902 ), and published his experiences in
various periodicals and books: “Die Fehlertabellen fiir Lichtdruck,”
in Jahrbuch (1895); Der Lichtdruck an der Hand- und Schnellpresse
(1898, 2d ed., 1906); Verschiedene Reproduktionsverfahren (1899);
Verschiedene Methoden des Lichtdruckes (1900); Der Lichtdruck
und die Photolithographic ( 1906) ; T echnischer Puhrer durch die Re-
produktionsverfahren (1908); and Die Reflektographie (1923).

Karl Albert, his son, born in 1878, succeeded him as professor at the
Graphische Lehr- und Versuchsanstalt, Vienna. He studied at the
Graphische Lehr- und Versuchsanstalt and did practical work in
graphic establishments in Prague, London, and as director of establish-
ments in St. Petersburg and Budapest. In 1920 the printing-ink manu-
facturing firm of Professor A. Albert & Son was founded. Karl Albert
was professor at the Graphische Lehr- und Versuchsanstalt from 1921
to 1927, when he was appointed government councillor and resigned
his professorship in order to act as technical advisor to industrial firms.
Hewrote,in 1926, the Lexicon der graphischenTechniken, andin 1927
the biography of Karl Klic, published by the Graphische Lehr- und
Versuchsanstalt. The Vienna family of August and Karl Albert are not
related to the family of the Munich phototechnicians Josef and Eugen
Albert.

PHOTOGRAPHIC ETCHING 621

THE USE OF ALUMINUM IN COLLOTYPY

August Albert of Vienna introduced, in 1896, thin aluminum sheets
as a substitute for glass base for the collotype film. Much later Maclure,
in Paris, also printed his collotypes from aluminum bases ( Jahrbuch ,
1 91 1 , P- * 7 6 )-

Transfers of collotypes on aluminum were also first employed with
cylinder presses by Professor August Albert at the Vienna Graphische
Lehr- Versuchsanstalt ( Phot . Korr., 1899, pp. 37, 112).

Chapter XCIII. photographic etching on

METAL FOR TYPOGRAPHIC PRINTING, ZINCOG-
RAPHY, COPPER ETCHING, AND THE HALFTONE
PROCESS

The use of zinc for relief etching was known as early as 1822, but
after that time zinc plates were also used largely for intaglio printing.
The obvious idea of applying the modified principle of lithography
to zinc relief etching 1 was probably first advanced by Blasius Hofei,
of Vienna ( 1 840) , who worked out the idea as a practical method and
offered it for sale to the Austrian National Bank, but without success.
It was not until 1 850 that Firmin Gillot, of Paris, brought zincography
into practice. He named his zinc relief etchings “paniconographs,”
which name soon went out of use, and the method of etching in relief
designs transferred to zinc was called “gillotage,” after the inventor.

In 1850 Gillot employed the photographic asphaltum method on
zinc plates for making photozincotypes. He took out a French “privi-
lege” on March 21, 1850, with a supplement March 15, 1851. The
original “paniconography” employed greasy ink transfers from litho-
graphs, autographs, copperplate engravings, or wood engravings onto
zinc plates, which were etched in relief with nitric acid after the so-
called French zinc relief etching process (see August Albert, Tech-
viscber Fiihrer durcb die Reproduktionsverfabren, 1 908, p. 1 84) .

Firmin Gillot (1820-72), a peasant’s son, had only an elementary
education, but was blessed with a healthy mind and ambition for work,
and having learned lithography, soon became one of the best workers
in his line at Chartres (France). He went to Paris in 1844 as a lithog-

622 PHOTOGRAPHIC ETCHING

rapher, and after 1 8 50 devoted himself untiringly to the improvement
of the process named after him. Gillot’s first idea was the transforma-
tion of a lithographic print into a typographic printing plate. He
succeeded in this by making a transfer with greasy ink on zinc from
an engraving or lithograph, etching the plain portions with acid, leav-
ing the greasy parts intact; thus he obtained a relief, and the zinc
plate became a typographic printing plate.

The Journal avantscene , realizing the great advantage which this
process offered to illustrated papers, gave up its wood-engraving de-
partment and entrusted Gillot with the reproduction of all drawings.
“Gillotage” soon penetrated so deeply into the practice that very
many illustrations which were formerly cut on wood were now pro-
duced by the photoetching process. Charles Gillot, his son, continued
the traditions of his father by improving the process invented by him.

The firm F. Gillot introduced in the sixties the commercial pro-
duction of photographic prints in greasy ink on chromated gelatine
paper and their transfer onto zinc plates, which were etched in relief
and printed typographically.

In 1872 Charles Gillot turned from the photographic transfer proc-
ess to a large degree and printed directly on zinc with albumen and
bichromate. The zinc plates coated with sensitized top were printed
under a negative, rolled up with greasy ink, developed in water, and
etched, after being dusted with resin.

During the years after 1850 Gillot instructed many pupils in zinc
etching at his establishment, and these spread his method more or less
intelligently.

Gillot printed not only from lithographs and intaglio copper etch-
ings on zinc for relief etching but also thin line prints from intaglio
etched steel plates produced by the photographic asphaltum process
and etched in a galvanic bath, as Baldus, in Paris, made them in 1854;
an example of this method was given in La Lumiere of 1854.

Negre, in Paris, was the first to make experiments in the production
of halftone pictures in zincography by transferring photographic
prints onto coarse-grained chromated gelatine tops (transfer with
greasy ink) . He joined Gillot, who transferred these collotypes 2 with
greasy inks onto zinc plates and etched them for typographic print-
ing. The first example of Negre-Gillot’s halftone zincography was
printed in La Lumiere, May 5, 1856, but was described in error by the
editor, Lacan, as made by the asphaltum process; it shows a grain re-

PHOTOGRAPHIC ETCHING 623

minding one somewhat of the coarse, worm-like collotype grain, and
on the other hand of the structure which forms in coating fissured
asphaltum layers.

Negre called his method “gravure paniconographique en relief,” and
it seems that he produced them for Gillot, who called his zinc relief
etchings generally “paniconographs.” In these plates one readily recog-
nizes the worm-like grain of Pretsch’s process, although the grained
chromated gelatine picture was not electrotyped, but was transferred
with greasy ink to zinc and etched in relief by Gillot’s method. Thus
one recognizes in these “paniconographs” the earliest methods of the
photographic halftone process on zinc with a natural grain in the
picture. Very few of these zinc etchings were produced, because the
method was, on the one hand, too complicated for practical use, and,
on the other, the pictures appeared too coarse.

At Vienna, in the early fifties, Karl von Giessendorf and the copper-
plate printer Tomassich (1859 or i860), at the Government Printing
Office under Auer, made experiments in etching on zinc, at first by
drawing with lithographic greasy ink on paper and transferring it on
zinc. In 1 865 Giessendorf produced for the first time halftone etchings
in relief from asphaltum prints on grained zinc, 3 but the tones were
coarse and the plates difficult to print.

The painter and photographer Karl Bapt. v. Szathmary, who had
produced an atlas of Rumania in which Carl Angerer (who was at the
time artist and technician at the Military Geographic Institute) col-
laborated, must be mentioned as one of the first to practice zincog-
raphy for printing maps (1862).

Carl Angerer, of Vienna, was of great service in introducing
and perfecting zincography. The fashion journal Iris, published in
Vienna in 1 865 or 1 866, was illustrated by “decalcography” by Carl
Angerer and Hugo Wiirbel, a pupil of Giessendorf. This method was
simple and permitted designs to be made on zinc. The zinc plates were
black leaded and coated with thin white gum arabic. The design was
scratched in through the greasy ink, and benzine was poured over the
plates. They were treated with water, dusted in with asphaltum, which
was melted, and then the design was etched on them. The journal
ceased publication; zincographs did not appeal to the illustrated comic
papers of the time. Carl Angerer, who was an excellent topographical
draftsman, went abroad, worked at Gillot’s, and returned to Vienna in
1869 to practice zincography.

624 PHOTOGRAPHIC ETCHING

Angerer, following Gillot, used prints on chromated paper for trans
fers in greasy inks onto zinc plates, but he changed Gillot’s method of
etching the photographic greasy ink images. In 1 870 he introduced in
his plant this new etching method, called it “chemigraphy,” and em-
ployed it for the reproduction of outline drawings.

Angerer’s etching process was later designated 4 as the “Vienna
etching method” by several technical writers. In his method Angerer
departed from the lithographic manner of treatment of wet zinc plates;
he etched very deeply on the first bite, and worked on a dry top, dusting
it with resins of different melting points.

For the production of halftone printing plates by zincography An-
gerer employed at first designs on a grained or cross-line paper, suitable
for transfer, drawn with a kind of lithographic crayon. This author
had to have recourse to such pictures, drawn on grained paper, which
were then etched on zinc, for the first edition of his book Die Moment-
photographie in ibrer Anwendung auf Kunst und Wissenschaft,
Vienna, 1884, and partly also for the second edition of this book, be-
cause at that time no one in Vienna was properly equipped to make
halftone zincographs.

Until the end of the eighties it was customary to make photozinco-
graphs from prints on bichromated gelatine paper, which were trans-
ferred from greasy ink prints on zinc. The little-sensitive asphaltum
process was seldom used. Angerer also used this transfer method, which
is particularly adapted to outline drawings, but less to the halftone
process. At this time the news came from America of the use of the
Levy cross-line screen and of direct printing from screen negatives on
zinc plates. The work was done either with chromated albumen solu-
tions or with the then novel American enamel-top method. Angerer
studied the process at the Central Bureau of Engraving in New York
(later owned by the translator) under F. J. M. Gerland, who patented,
on October 3, 1893, the first high-light process. Angerer introduced
in his establishment in Vienna screen negatives printed on chromated
albumen enamel tops, because glue tops, necessitating great heat in
burning, were not suitable for the soft Belgian and Silesian zinc. [(In
America a hard zinc was used.— Translator/]

Angerer, one of the most successful pioneers of zincography, was
born the son of an innkeeper at Vienna, 1838; he learned lithography
and printing, and experimented early with the etching of zinc printing
plates. In 1859, while serving in the army, he was assigned to duty at the

PHOTOGRAPHIC ETCHING 625

Military Geographic Institute, Vienna, where he worked as artist,
lithographer, and copperplate engraver. After leaving the institute he
went to France and Belgium, where he studied the chemigraphic
methods. After his return to Vienna he founded, in 1 87 1 , his chemi-
graphic establishment, in which he introduced photozincography and
photolithography with the transfer method then customary. His
brother-in-law, Alexander Goschl (died 1900) entered the firm in
1874 as business manager. The firm was granted the title Court Art
Institute and became famous in the development of photomechanical
processes. Imperial Councillor Carl Angerer was an honorary member
of the Photographic Society of Vienna. He died in 1915, at Vienna. 5
His son, Commercial Councillor Alexander Angerer, continued the
business of the firm Angerer & Goschl.

When Meisenbach invented his halftone process, Carl Angerer rec-
ognized its importance and improved on it, taking out patents which
involved him in a patent suit with Meisenbach. But this method was
soon surpassed by the halftone process with the cross-line screen (Ives,
Levy), which Carl Angerer introduced in masterly fashion in his plant,
which soon became one of the largest in Europe. He possessed the splen-
did ability, at a time when there existed no technical schools for this
craft, to educate his workmen in his plant to such competence that
many of his apprentices later entered business for themselves, like Pat-
zclt, Andreas Krampolek, and others.

Without doubt the greatest influence on illustrations for use with
all forms of printed matter was contributed by photography through
the invention of halftone printing plates, which could be incorporated
into the text in printing forms. The purely photographic methods of
this kind, which were known in the seventies, were so imperfect that
it was preferred to make drawings on so-called “scratchboard” with
transfer ink, greasy crayons, or india ink, after which the drawings
were mechanically transferred to zinc and etched. Such scratchboard
was put on the market by the English firm Maclure and Macdonald of
London, about 1870, for lithographic purposes. Carl Angerer im-
proved the paper, and it is due to him that crayon and scratchboard
drawings were introduced in book illustration. He took out, on July
5, 1877, an Austrian “privilegium” on his scratchboard method, which
was and still remains the best of its kind, and many artists of that period
(Katzler, Klic, Juch, Weixelgartner, and others) made use of such
paper for their drawings.

6z6

PHOTOGRAPHIC ETCHING

In 1880 Angerer first offered for sale scratchboard with cross-line
ruling, especially suitable for drawings to be reproduced for printing
plates. As late as 1880 it was the preferred method, in illustrating the
text of books and periodicals, for making drawings of photographs and
pictures of all sorts on grain, screen, or scratchboard with greasy cray-
on, transferring them onto zinc, thus producing chemigraphic relief
etchings.

The technique of these halftone drawing methods furnishes the
transitory period of photoengraved halftone plates, originating from re-
drawn copies on scratchboard, to the modern purely photographic
halftone process for typographic printing, called on the Continent
“autotype.” 8

INVENTION OF THE HALFTONE PROCESS

The breaking up of pictures into halftones by the use of meshes or
screens was hardly considered in the middle of the nineteenth century,
although the ingenious Talbot recommended in 1852 the printing of
a mesh between the negative and the heliographic plate in order to
obtain halftone printing plates ( Handbuch , 1 899, IV, 497 ) . In Talbot’s
patent there are mentioned glass plates and woven meshes with fine
opaque lines or very fine grain, and therefore the honor of the invention
of a gauze line or grained screen belongs to Talbot (185 2). 7 Talbot
also mentioned that his heliographic etching and screen process could
be employed on zinc or lithographic stone as well as on steel.

Single-line screens are described in the French patent of M. Berch-
told, December 14, 1857. 8 He used glass plates coated with an opaque
substance, through which the parallel lines were scratched. Either the
glass plates were placed on the metal coated with light-sensitive as-
phaltum and crossed after half the exposure, or a copy was made by
a double exposure of the lines to get the cross-line effect, and from
this cross-line dry plate the screen was printed on the metal. J. C.
Burnett reported in 1858 methods of line screen photography with
single-line and cross-line screens. 9 The use of a woven mesh for produc-
ing the screen effect on halftone printing plates was mentioned in Tal-
bot’s patent of 1852; he used copied meshes. Silk gauze, canvas, mos-
quito nets, wire nets, etc., are mentioned as suitable for screens by sev-
eral early experimenters. 10

An English patent (No. 2,954) was granted on November 17, 1865,
to the brothers Edward and James Bullock. They first made a dia-

PHOTOGRAPHIC ETCHING 627

positive, placed it in contact with the screen (for instance, gauze), and
then photographed the image which had been broken up by the com-
bination of positive and screens. These “reticulated negatives” were
printed on transfer paper (bichromated gelatine method), and from
this they produced printing plates for any of the known processes.
They also used the single-line screen for exposures in the camera.

A method, which is not quite clearly described, for the production
of screen images for printing plates was announced by Frederik von
Egloffstein in his British patent of November 28, 1865 (No. 3,053) j 11
he also took out a patent in America; 12 it seems that he used a steel
plate on which very fine lines were engraved, which probably were too
fine to be employed with success. 13

A great impetus was given to the process of making typographical
printing plates by J. W. Swan, who makes the following important
statements in the patent specifications 14 of his “photomezzotint prints”:
In order to obtain from an ordinary negative halftone printing plates
with a chromated glue top and an electrotype in relief, he (Swan)
provides the surface of the plate with a series of parallel, equidistant
lines or lineatures which cross each other, for the purpose of enabling
the surface of the plate, thus broken up into numerous lines and dots,
to retain the printer’s ink.

He states elsewhere: These lineatures or dots which must be equidis-
tant or nearly so “I make in or on the negative itself” or “I make these
lines or dots on the collodion film on which the chromated glue re-
lief is produced.” This demonstrates that Swan went beyond Talbot’s
recommendation and had in mind the production of screen negatives;
he also mentions that he produced lineatures with a machine on a glass
plate coated with an opaque ground and “from it produced a negative
in the ordinary manner”; furthermore, he also mentions grain plates
(instead of lineatures) obtained with powdered resin. However, he
does not speak in this discussion of the importance of such glass screens
or their insertion in the path of the light in the camera in front of the
sensitive plate.

Waterhouse experimented with photo-zincographic halftone print-
ing plates in 1868, making prints on chromated gelatine paper with
greasy printing ink and transferring them to grained zinc. 15

William August Leggo and George E. Desbarats printed a negative
on a grained film, which they then transferred on stone or zinc (British
patent, May 25, 1871, No. 1,409). The Daily Graphic of New York

6z8

PHOTOGRAPHIC ETCHING

used “leggotypes” for illustrated inserts in 1873; they were made by
printing the negative on a mesh film and transferring it onto zinc. By
another method, which was called “helio-engraving” or “photo-en-
graving” and was practiced from 1873 in America, it is asserted that the
screen was placed before the negative plate during the original ex-
posure, but the author was not able to present proofs of this claim. By
the end of the last century various kinds of screen and grain methods
for photographic typographic printing plates had been invented.

APPLICATION OF THE SCREEN PRINTING PLATE TO NEWSPAPER PRINTING

The brothers Moritz and Max Jaffe, of Vienna, turned back to
Talbot’s gauze, which they interposed in the camera in front of the
sensitized plate. On March 1, 1 877, they were given a “privilegium”
for a photo-zincographic process using such a screen, in which they
expressed the idea of producing screen negatives in the camera by
stretching miller’s gauze in the plateholder close in front of the silvered
plate during the photographic exposure.

It must be stressed that the brothers Jaffe produced in 1877 these
halftone printing plates for newspaper printing, exhibited proofs of
them, and made them public. Stephen H. Horgan, New York, claims
priority in the production of the first halftone printing plate for news-
paper printing as of March 4, 1880, but the brothers Jaffe preceded
him by three years. The use of these gauzes and nettings, however,
furnished only mediocre results. Moritz Jaffe, the business manager
of the firm, died in 1880, and Max Jaffe continued the business, ex-
tending it considerably for photogravure, zincography, photolithog-
raphy, and three-color collotypes.

Max Jaffe was born in 1845 in Mecklenburg-Schwerin. 16 He was the
son of a merchant, finished Latin school in his home town, and studied
drawing and painting in 1864 at Nuremberg (Bavaria). He went to
Paris in 1865, where he worked with the photographer Reutlinger and
in other studios for several years. At Hamburg he worked from 1868
to 1869, where he designed a new construction for portrait and sculp-
tors’ studios. 17 Then he went to Vienna, worked in Lowy’s and
Rabending’s photographic galleries, and established his own plant for
the photographic reproduction processes. He was the first to produce
in Austria and Germany (1877) halftone screen printing plates for
typographic presses with negatives from nature. With August Albert,
at Vienna, he manufactured a photolithographic gelatine transfer paper

PHOTOGRAPHIC ETCHING 629

(1886). They published, probably were the first to publish, the addi-
tion of acetone to the bichromate bath used for sensitizing gelatine
paper, in order to accelerate the drying (Phot. Mitarbeiter, 1886, p. 90) .

After the Graphische Lehr- und Versuchsanstalt, Vienna, was
founded, Jaffe served there as lecturer and demonstrator of the re-
production processes until 1889. He wrote many technical articles.
In 1893 Jaffe invented “Weitraumphotography” (Phot. Korr., 1904,
1918), and in 1918 the “Akaustisches Verfahrens,” in which plano-
graphic printing is executed from lithographic stone or metal without
etching or similar means.

VARIOUS EXPERIMENTS FOR THE PRODUCTION OF HALFTONE RELIEF
PRINTING PLATES

Charles Petit, at Paris (died 1921), and F. E. Ives (1856-1937), at
Philadelphia, invented at the same time a process for the production of
halftone printing plates (from halftone negatives and chromated gela-
tine reliefs, plaster of Paris casts, and ruled with a wedge-shaped tool) .
Petit was granted a patent in 1878 and Ives eight days later.

The early process of Petit was soon dropped by him, but the name
“similigravure,” 18 coined by him, is still used in France for those
methods, which they also call “photogravure a demiteintes,” while in
Germany the name “Autotypie” is used.

Swan received an English patent in 1 879 for a new process in relief.
He broke up the halftone either by a screen printing method or by
exposure with the screen placed in front of the sensitive plate or in
front of a diapositive. In every case the screen was crossed at a certain
angle during the exposure. This method was recommended by Swan
also for the chromate process on zinc, copper, and so forth.

For further details concerning the various earlier but now obsolete
halftone processes, such as Ives’s photoblock method (patent 1878),
Mosstypes, Petit’s similigravure, see Jahrbuch (1887, p. 332) and Grebe
in Zeitschrift fiir Reproduktionstechnik (1899, p. 19).

Horgan introduced a process for making photographic halftone
plates for newspaper printing, at New York, in 1 880. He was employed
as photographer by the New York Daily Graphic and had devoted
himself to the photomechanical processes since 1875. He covered a
sheet with cross lines and placed it between the halftone negative and
photolithographic chromated gelatine paper, washed it, rolled it up
with photolithographic ink, transferred it to zinc, and etched the plate

63 o PHOTOGRAPHIC ETCHING

to type height. The Daily Graphic printed, March 4, 1880, a portrait
from life of Henry J. Newton, president of the American Institute.
This was one of the earliest applications of this method to newspaper
printing.

In the Inland Printer of 1924 we find an article: “The Beginnings
of Halftone, from the Note Books of Stephen H. Horgan,” by Lida
Rose McCabe. There is a reference to Horgan’s first cross-line plate
by an interposed screen of “A Scene in Shantytown, New York,”
which was printed in the Daily Graphic on March 4, 1880. According
to Anthony's Photographic Bulletin (1880, p. 123) this invention was
presented at a meeting of the Photographic Section of the American
Institute. But the screen halftone printing plate of Horgan was no
“Halftone plate” in the strictly technical sense of the word.

A remarkable attempt at cross-line or grain screen printing on unex-
posed gelatine silver bromide plates before exposure in the camera for
making the negative we owe to Brunner & Co. in Winterthur, Switzer-
land, (German patent, No. 31,537, Jan. 29, 1884).

The inventors hoped to place every photographer in a position in
which he could make screen negatives with the ordinary photographic
equipment and thus be able to produce halftone printing plates. Such
gelatine silver bromide plates were actually produced for the market.
These Brunner silver bromide plates hardly fulfilled their purpose,
because printing of the screen cross lines in close contact with the
gelatine silver bromide film produced no proper breaking up of the
screen image into dots of different sizes. The method was more suitable
for grain screens, which required no screen distance, but the method
soon went into disuse.

GEORG MEISENBACH’s HALFTONE PROCESS ( I 882 )

Meisenbach, of Munich, achieved great success with his “Auto-
typie.” 18 He eliminated the defects caused by the irregularities of the
earlier used lineatures by (German patent, No. 22,444, May 9 , 1882 )
making a diapositive from the copy, bringing it in contact with a
parallel single-line transparent screen, turning the plate when half-
exposed ninety degrees, and finishing the exposure, which produced
cross-lines on the negative. Later, Meisenbach also made halftone nega-
tives direct from the copy by the interposition of a single-line screen
in front of the sensitized glass plate and crossing it after a half-exposure
at 90° (Phot. Korr., 1883 and 1884); but this last procedure of mak-

PHOTOGRAPHIC ETCHING 631

ing halftone negatives is not contained in the patent specification.

Meisenbach’s methods, which he introduced into practice after he
had equipped an establishment for “Autotypie” in Munich, contributed
greatly to the progress of the halftone process for typographical print-
ing. To his partner, Baron Schmadel, we owe the name, “Autotypie”
which has become the everyday trade name.

At first Meisenbach made his single-line screen photographically
on wet collodion plates from a copperplate print of a ruled copper plate.
Baron Schmadel succeeded, in 1884, in ruling the first glass screen
(with a specially constructed ruling machine) directly in the black
coating of a glass plate, and from this time dates the success of Meisen-
bach’s autotype. The Meisenbach patent was sold in the same year in
England, and a branch of the Meisenbach Company was established in
London.

Georg Meisenbach was born in 1841 at Nuremberg, Bavaria, and
became a copperplate engraver. As such he achieved success, especially
with his architectural subjects. In 1873 he moved to Munich, founded
there the first zincographic etching shop, and began in 1879 his experi-
ments with the direct reproduction of halftone pictures with a screen.
After the year 1889 all halftone negatives at Meisenbach’s plant were
made with cross-line screens, although nothing was published about
this, because at that time the working procedure was still kept secret
as much as was possible.

In the spring of 1891 Meisenbach retired, owing to ill health, and
the business was continued by his son and Baron Schmadel. In 1892
came the merger of Meisenbach’s Autotype Company with H. Rif-
farth & Co., Berlin. 20 Meisenbach withdrew to his country estate, near
Munich, where he died December 12, 1922.

Meisenbach’s halftone, “Autotypie,” was the first photographic
halftone process for book printing which was made commercially
practicable. The use of it continued until about the end of the eighties
in its original form, when it was definitely displaced by Ives’s halftone
process with cross-line screens.

PATENT SUIT MEISENBACH - C. ANGERER

Angerer and Goschl, Vienna, invented at the same time a half-
tone method which was simpler and cheaper than the original Meisen-
bach method. They produced by this method, in 1879, relief printing
plates from photographs and wash drawings. They interposed during

PHOTOGRAPHIC ETCHING

632

the exposure the single-line glass screen in front of the sensitive plate
in the camera, turning it by 90° after half of the exposure. By this
manipulation they undoubtedly produced directly a cross-line nega-
tive, without first making a screen diapositive, thus simplifying the
process.

Angerer patented his halftone method in Austria, France, and Eng-
land in 1 884; in Germany the patent was denied, owing to Meisenbach’s
objection, who proved that he had previously invented this simplication
and had practiced it. 21

IVES INTRODUCES MODERN CROSS-LINE SCREENS ON GLASS FOR
MAKING HALFTONE NEGATIVES ( I 886)

In 1886 the American Frederic Eugene Ives introduced the modem
cross-line screen on glass for the production of halftone negatives for
halftone relief printing plates and captured with it permanently the
field of the halftone process. Ives devoted himself from 1878 to experi-
ments for the production of halftone relief printing plates, and ruled
his plates in the beginning mechanically. 22 He became dissatisfied with
this mechanical method of halftone etching and commenced in 1 88 1
experiments to produce ruled printing plates by the optical method
with single lines.

Ives promoted the halftone process by basically correct methods
and is considered the founder of the modern halftone process. For a
short period he used the single-line screen, and he exhibited in 1885
such pictures at the Novelties Exhibition in Philadelphia, in which
the single-line lineatures produced lights and shadows by their varying
thickness. In 1 894 Ives recortimended this procedure for the three-color
halftone process, although he had long since worked with cross-line
screens.

Ives had recognized in 1886 the advantage of two single-line screens,
superimposed on each other so that the lines crossed at 90° and
cemented together. He made them at first on a photographically
blackened collodion plate with a ruling machine.

By the interposition of crosswise superimposed and cemented single-
line glass screens in front of the photographic plate in the camera Ives
produced screen negatives, from which etched copper relief printing
plates by the glue enamel process were made . 23

These halftone relief printing plates were quite practical for print-
ing on rapid typographic presses, but the cross-line screens required

PHOTOGRAPHIC ETCHING

6 33

improvement. Max Levy, also of Philadelphia, succeeded in 1890 in
perfecting glass screens. Levy coated glass plates with an etching
ground, in which he ruled parallel lines with a ruling machine; he
etched the lines rather deeply with hydrofluoric acid, removed the
ground, filled in the etched lines with a black resin, and polished the
surface. The line screen appeared sharp and clear. Two such single-
line screens were placed at right angles and cemented together. These
Levy screens met with great success in the halftone process. They were
put on the market in 1888 with rulings of various degrees of fineness,
proved to be the best of their kind, and achieved general use and
approval.

Max Levy, born in Detroit (1857) of German-Bohemian parentage,
was a photographer who went to Baltimore, where he established,
jointly with his brother Louis Edward Levy (d. 1919), in 1875, a
photographic plant for reproduction processes. From 1881 to 1885
they made zincographs by direct printing on the bichromated albumen
coated metal and etching it. Then Meisenbach’s single-line screens
were introduced. Max Levy improved in 1888 the ruling machine,
producing perfect cross-line screens, etched in glass (halftone screens)
in various finenesses of lines for sale. Max Levy at first ruled the glass
plates diagonally in order to have as little waste as possible. The
brothers Levy also invented an etching and powdering machine for
zinc line plates and later an etching machine for halftone plates. One
of the zinc etching machines was exhibited at the Paris Exposition of
1 goo . 2 ' 1 Max Levy took out numerous patents, among them one for a
four-line screen.

The American cross-line screens were brought by Fritz Goetz to
Europe in 1 890. They were first introduced by Meisenbach, Munich,
then by Angerer and Goschl, Vienna; E. Albert, Munich; Husnik,
Prague; and by others for practical use in the halftone process.

Frederic Eugene Ives was born in 1856 in Litchfield, Conn., and
died at Philadelphia in 1937, at the age of eighty-one. He learned the
printing trade, was employed in a printing plant at Ithaca, N. Y., where
he devoted himself to amateur photography, and when only eighteen
years of age he became the official photographer (1874) of Cornell
University, Ithaca, New York, where he remained until 1878, after
which he turned to the development of the photomechanical processes.
He began at first to resolve the photographic chromate gelatine re-
liefs into lines and dots by a mechanical method and introduced this

PHOTOGRAPHIC ETCHING

6 34

into practice at the Crosscup and West Engraving Company in Phila-
delphia, where he also produced halftone plates for printers; later he
pioneered the improvements of the halftone process with the cross-
line screen (optical resolution of tone pictures into lines and dots). He
invented the burning-in method of chromate glue (American enamel
process) for copper halftone plates. He made public his three-color
process (“composite heliochromy”) in 1888, which he patented in
1 890. Later he went to England and visited also Vienna; while there he
made Europe acquainted with his “photochromoscope,” which was
the first instrument producing really good results by the additive three-
color process. He made apparatus not only for projection but also for
direct vision, so that we may say that he improved all forms of three-
color photography.

His son, Dr. Herbert E. Ives, of New York City, himself a promi-
nent scientist in the field of photographic physics, founded in 1928,
in honor of his father, an honor medal for the American Optical
Society, to be awarded for distinguished work in the field of optics
journal of the Optical Society of America, 1930, XX, 161).

Many years passed before Europe could produce screens as excellent
as those of Max Levy (J. C. Haas, at Frankfurt a. M., E. Gaillard, at
Berlin, and others) . The cross-line screen can only attain its full effect
and properly resolve the picture into harmonious lines and dots when it
is used at the right “screen distance” from the sensitive plate and when
the lens is properly diaphragmed. It is only when the pertinent optical
conditions are correctly known, considered, and applied that satis-
factory halftone negatives can be produced, such as are demanded for
the process of today. Although empiric experience gradually led to the
proper use of diaphragms and screen distances, a scientific system was
only attained when the correct theory of the process was established.
The first thorough study of the theory of the halftone screen in pure
geometric presentation we owe to the Surveyor General of Canada,
E. Deville, who lectured before the Royal Society of Canada on May
1 7, 1 895, on the “Theory of the Screen in the Photomechanical Pro-
cess”; the lecture was published in the journal of the society. 25

During the first stage of Meisenbach’s halftone process the work
was done with the zincographic transfer method (from chromated
gelatine paper) ; but this transfer image was not sharp enough when
fine screen lines were used. America undoubtedly turned first to direct
printing on metal. The asphaltum process was not sufficiently sensitive

PHOTOGRAPHIC ETCHING 635

and was abandoned for the chromate process. An improvement in
precision of the etching procedure was brought about by the introduc-
tion of the enamel process, which could be executed easily and with
certainty.

Ives is acknowledged as the inventor of the American enamel pro-
cess. In this process a copper plate is coated with bichromated glue
solution, which is dried, printed under a cross-line screen, developed
in water, dyed in a methyl violet bath, burned, and etched with iron
chloride. It is in this method that Levy screens achieved their best effect.

Before the introduction of his enamel process at the Crosscup and
West plant in Philadelphia, Ives made relief copper printing plates
with cross-line screens (1888) and started a plant for their production,
printing negatives directly on glue tops, 26 burning-in the prints, and
etching them with iron chloride. H. W. Hyslop 27 claimed priority in
the invention of the copper enamel process, but it seems that Ives
achieved practical results from this process earlier than others.

The American copper-enamel process with Levy screens was soon
practiced in Europe by many establishments; we cite, for instance,
Boussod and Valadon in Paris (1886).

Copper and brass plates resist the burning-in of the bichromated
glue image better than other metals and therefore were preferred for
the process. Zinc plates often become crystallized during the burning-
in, do not etch well, and are too soft to be printed from directly,
which for a time relegated zinc to the background, until a cold enamel
was introduced much later. However, through the introduction of a
cadmium zinc alloy and a suitable nitric acid solution, zinc plates were
eventually adapted to the halftone enamel process. Professor Franz
Novak of the Graphische Lehr- und Versuchsanstalt, Vienna, experi-
mented 28 with this metal and found that some kinds of American zinc
contained the right amount of cadmium for this use, but that any zinc
might be adapted for the process by making an alloy of zinc with
small amounts of cadmium. The trade, however, never used this dis-
covery.

It is quite possible to produce any kind of fine screen halftones on
polished zinc plates without the burning-in over great heat, by using
an albumen ammonium bichromate top. Such prints on zinc are rolled
up with greasy ink and developed in water. This produces a somewhat
sticky image, which is dusted with resin and heated slightly until the
resin melts. The structure of the zinc is not changed by this operation,

PHOTOGRAPHIC ETCHING

636

and halftone prints of finest screens can thus be etched on zinc with-
out difficulty. This method also started in America and was probably
well known to Ives.

HALFTONES WITH GRAIN SCREENS

The use of a grain on prints from negatives or diapositives for half-
tone printing is very old. When the method used in the halftone proc-
ess, interposing a screen during the exposure of the negative in the
camera, became known, the old idea of using grain screens turned up
again. Several of these experiments were carried on at the turn of the
nineteenth century with more or less success.

Max Perlmutter, a photoengraver at Vienna, made grain halftone
plates by melting an aquatint grain of powdered asphaltum on a glass
plate, or by a transfer from a fine grained lithographic stone with
greasy ink on glass and then dusting it in with the finest possible
asphaltum powder. These grained glass plates were interposed closely
in front of the collodion plate during the exposure of the negative,
just as in the halftone process. Perlmutter exhibited successful prints
from such grain halftone plates at the Paris Exposition of 1900. The
method found only a limited application, because the grain plates were
more difficult to print than halftone plates. The method, however,
was still in use in 1910. The firm J. Lowy, of Vienna, used this method
in producing a brass halftone plate with Perlmutter’s grain screen,
which was printed in the Phot. Korr., 1910.

The firm of J. C. Haas, Frankfurt a. M., introduced in 1900 a grain .
screen made by them independently from asphaltum powder. Jahr-
buch for 1901 shows proofs of such screens.

But the reproduction of the halftones by these grain screens was
never as satisfactory as reproduction with the Levy cross-line screens. 20

A remarkable substitute for the above-mentioned black grain screens
was invented by the Englishman J. Wheeler, who took a patent (Brit,
patent, No. 12,017, May 14, 1897) on such uncolored grain screens
etched in glass (“mezzograph screens”). They were produced by
subjecting glass plates to the smoke of smouldering birchbark, which
formed a deposit of fine drops on the surface of the glass. Etching
with hydrofluoric acid produced a delicate, irregular grain structure
on the glass, owing to the differing resistance of these drops. The in-
ventor at first used this mezzograph screen only for graining half-
tone silver chloride prints. The first halftone mezzotint printing plates

PHOTOGRAPHIC ETCHING 637

were made at the Graphische Lehr- und Versuchsanstalt, Vienna, with
one of these screens, brought to the author by the inventor, and a print
is shown in Phot. Korr. (1899, p. 717). The Wheeler mezzograph
screen appears almost smooth to the touch, but when interposed close
to the photographic plate during exposure, it produces a grain negative,
which when printed on metal can be etched to a printable depth. Of
course, printing these plates on both flat and cylinder presses requires
a great deal of careful manipulation.

Husnik and Hiiusler’s phototechnical art establishment at Prague
(Czechoslovakia) carried out the same idea as that of Wheeler. They
printed a worm-like grain from collotype plates on plate glass, which
produced black grain screens, but which did not satisfy Husnik. 30
When Husnik and Hausler, however, etched the worm-like grain with
hydrochloric acid into glass, and, after removal of the black film, inter-
posed this seemingly almost smooth glass screen during exposure in
the camera, they obtained fine, printable grain halftones similar to
those produced with Wheeler’s “mezzograph” screen.

Here must also be mentioned the halftone typographic printing
plates produced with powdered asphaltum, according to Klic’s photo-
gravures; they were made in the same manner by the transfer of a pig-
ment image, with the difference that he printed from a negative. Klic
produced such plates on copper, called “cuprotypes,” about 1880.
About 1886 Roese made such plates at the Government Printing
Office, Berlin, on brass and named the method “chalkotype” ( Hand -
buch, 1922, IV(3), 67).

The artist and painter Emanuel Spitzcr, at Munich, applied in 1901 31
for a patent, which was not granted until July 7, 1905 (No. 161,91 1 ),
for a process under the title “Spitzertype.” He had observed that in
certain circumstances light-sensitive layers are formed by mixtures of
glue and gum arabic with bichromates, which form automatically after
drying a hardly perceptible grain internally. When direct prints on
such tops, from ordinary halftone negatives (without first washing
them in water), are etched in the copper plate, they show underneath
a so-called “automatic” or “spontaneous” grain and can be printed on
typographic presses.

Emanuel Spitzer (1844-1919) was a clever illustrator who went to
Paris in 1 864 and was stimulated by the work of P. Gavarni and H.
Daumier. He moved to Munich in 1869, where he was employed as
illustrator on the Fliegenden Blatter, a comic journal, and later turned

6 3 8 PHOTOGRAPHIC ETCHING

successfully to painting. His work was frequently printed in peri-
odicals, and because the reproduction did not always satisfy him, he
devoted himself intensively to the problem of reproduction. This re-
sulted in his invention. He founded, with Dr. Robert Defregger, the
Spitzer Company, at Munich, which in a publication Die Spitzertypie,
ein neues Reproduktionsverfabren (Munich, 1903) printed fine speci-
mens of the process. In 1 907 this company produced their first three-
color prints. The method must be considered the simplest process for
the production of halftone printing plates from continuous tone nega-
tives ( Handbuch , 1922, IVX3), 63).

Spitzer was not able to enjoy the fruits of his invention undisturbed.
In addition to Dr. Defregger, another associate joined them, Dr. Hans
Strecker, who engaged his friend Karl Blecher as manager of the
laboratory. Strecker and Blecher elaborated a process under the name
“stagmatype,” which they patented on November 26, 1908 (No.
231,813). The claim described a method of producing printing plates
with grainy structure by etching with iron chloride a bichromated
glue top on metal, such as copper, which was exposed to light, but not
washed in water. This same matter is also described in the English
patent of H. Strecker- Aufermann (Brit. Jour. Phot., 1910, p. 179;
Eder’s Jahrbuch, 1910, p. 574), without adding any essential new
feature to the Spitzertype method.

This author proved that Spitzertypes and stagmatypes are essentially
identical. A distasteful controversy between Strecker and Spitzer,
during which Strecker played a questionable role, established the right
of Spitzer’s priority. (Phot. Korr., 1912, p. 101; 1913, pp. 330, 389,
464; 1917, p. 247; Zeitschr. f. Reproduktionstechnik, 1912, pp. 69,
107; see also , Handbuch, 1922, IV (3), 63). This litigation in the courts
forced the Spitzer Company into liquidation in 1909. Spitzer was taken
ill and lost the strength which would have been necessary to improve
and exploit his process. His invention remained unused and forgotten
for years, but a short time ago his wife and daughter sought to revive it.

In order to complete the record it must be mentioned that according
to L. P. Clerc, Paris, H. Placet announced in 1877 that mixtures of
glue, gum arabic, and bichromate show a grain formation when thin
layers of the mixture dry out. Clerc refers to L. Vidal’s book Photo-
gravure (Paris, 1900, p. 330). But we must call attention to the fact
that Placet was not aware or at least did not mention the possibility of
producing halftone printing plates on copper by etching such print
tops with iron chloride.

Chapter XCIV. three-color photography

Printing books in color reaches back to 1457 and was used by Peter
Schoffer (1425-1502), Mainz, assistant to Gutenberg and Fust, who
employed it for his Psalter, but it was replaced in later years by hand
painting, owing to the inefficient accessories. Of course this color print-
ing, or rather variegated printing, was at first only a printing next to
each other of colors, not a superimposed printing. 1 Ever since Sene-
felder invented lithographic printing, color printing was carried on
almost entirely by lithography; colors were printed on top of each other
as well as next to each other. The knowledge of the so-called primary
colors led gradually to modern color printing.

The first statements on primary colors, which are the basis of all
our sensitivity to color, 2 were made by Antonius de Dominis in his
dissertation De radiis visus et lucis in vitris perspective et Wide (V enice,
1 6 1 1 ) . He observed that colors result from the absorption of white
light. Black is the absence of light, he states, and red, green, and violet
are the primary colors, of which all other colors are composed (the
still valid color system of complementary three-color synthesis) .

The Jesuit Franciscus Aguilonius, who published a dissertation on
optics in 1 6 1 3, drew a kind of color scheme, taking as a basis the primary
colors, red, yellow, and blue, showing the basic colors in circles, half
of which showed them in combination, thus indicating the synthesis.
The Englishman Waller made investigations in 1686 in subtractive
color syntheses, that is, mixing pigment colors. Sir Isaac Newton, as
is well known, dissected light in the color spectrum and added red,
yellow, and blue in order to produce white (additive color synthesis) .

The first practical three-color printing with red, yellow, and blue
inks was dbne by Jakob Christoph Le Blon, bom at Frankfurt a. M.,
in 1667. He studied painting and copperplate engraving under Carlo
Murates, went to Rome, and later to Amsterdam. Here he devoted him-
self, incited by Newton’s theory, to the task of printing copperplate
engravings in color, by using seven plates successively on top of each
other in Newton’s colors (red, orange, yellow, green, blue, indigo,
violet). Naturally this lengthy procedure must have caused Le Blon
great difficulties, and he endeavored therefore to reduce the number
of printing plates. Finally, he arrived at the conclusion that all possible
shades of color could be obtained by printing from only three plates,
using red and yellow and blue printing inks. He went to London and
published, in 1722, the first report on his color printing process under

640 THREE-COLOR PHOTOGRAPHY

the title, II color itto; or, The Harmony of Colouring in Painting, Re-
duced to Mechanical Practice under Easy Precepts and Infallible Rules.
Le Blon’s announcement, however, met with little success, probably
because his statements were rather obscure. It was only after he moved
to Paris, in 1737, that he found a number of pupils and a public which
was intensely interested in his efforts. In 1740 the king of France
granted him a subsidy under the condition that he should demonstrate
his method before a commission, engrave and print the plates in their
presence, and reveal all the secrets of his art. Le Blon died in 1741 at
Paris, 74 years of age, after having devoted his whole life, full of anxiety
and labor, to his invention of three-color printing.

Color printing (chromolithography, etc.) which started to flourish
again at the beginning of the nineteenth century, reattracted attention
to the laws of combining colors. Heinrich Weishaupt printed, in 1835,
after many years of experiments, the first three-color lithograph
(“Head of Christ,” by Hamling).

Blasius Hofei, at Vienna, introduced in the middle of the 1 820’s book
printing in colors by means of several woodcuts. He was followed by
Heinrich Knofler, in Vienna (1868), who used as many as fourteen
to twenty woodcuts (Friedrich Jasper, “Der Farbendruck in Oster-
reich,” Neue Freie Presse, July 12, 1930).

Another primary-color system, consisting of red, green, and violet
on the basis of additive mixture tests was introduced by Chr. Wiinsch,
in 1 792, 3 which became the foundation of the famous theory of color
sensation by Thomas Young. 4 Young asserted that the normal human
retina possesses three different kinds of nerves, which, when stimulated,
cause a reflex of the respective nerve elements sensitive to red, green,
and violet. This theory was developed further by Helmholtz, 5 Maxwell,
A. Konig, Franz Exner, and others.

Another direction was taken by Sir David Brewster, 8 who, led
astray in 1831 by color tests on a subtractive basis, proposed the theory
that only three homogenous colors exist in the spectrum— “red, yellow,
and blue”— and that each of these lights gave rays of each, refrangible
within the limits of the spectrum. This view was, however, soon scien-
tifically disproved, especially by Helmholtz, 7 but printers accepted
Brewster’s colors in practice, because in the present state of color
ink manufacture only yellow, red, and blue produce suitable mix-
tures, especially in the yellow shades.

The famous English physicist J. Clerk Maxwell was the first to

THREE-COLOR PHOTOGRAPHY 641

think of color reproduction by means of three-color light filters, and
he published his idea in a lecture “On the Theory of the Three Primary
Colours” before the Royal Institution, London, May 17, 1861. 8 He
discussed Young’s theory of the so-called primary colors, which in
various combinations give all the colors of the spectrum. Among his
experiments Maxwell made a projection of partly drawn and partly
photographically produced diapositives behind red, green, and blue
light filters:

Three photographs of a coloured ribbon taken through three coloured
solutions, respectively, were introduced into the lantern, giving images
representing the red, the green, and the blue parts separately, as' they
would be seen by Young’s three sets of nerves, respectively. When these
were superposed, a coloured image was seen, which, if the red and green
images had been as fully photographed as the blue, would have been a
truly coloured image of the ribbon. By finding photographic materials
more sensitive to the less refrangible rays, the representation of the col-
ours of objects might be greatly improved.

This demonstrates that Maxwell (1861) was the first to prove the pos-
sibility of reproducing colors by photographic three-color negatives
made through color filters. Although his experiments confined them-
selves principally to diapositives, he also mentioned explicitly colors laid
on paper, stating that “by means of the colour scale (Young’s primary
colours) one could obtain colour equations for coloured paper . . .
which present the numerical value of the whole of each colour in the
proportion in which it was admixed.”

James Clerk Maxwell (1831 -79) 0 studied at Trinity College, Man-
chester, until 1854, became professor at Aberdeen in 1856, at King’s
College, London, in i860, resigned in 1865, and retired to his estate in
Scotland until he was called to the University of Cambridge in 1871
as professor for experimental physics, where he died. He devoted him-
self to astronomy, electricity, magnetism, and optics, and his scientific
works have become of the utmost importance. 10 Maxwell has become
famous especially through the establishment of his electromagnetic
light theory. According to the undulation theory of light, light waves
are caused by elastic vibrations of the ether. According to the electro-
magnetic light theory light waves are not of an elastic but of an electro-
magnetic nature. The first indication of a relationship between the
motion of light and electromagnetic phenomena were found in the
facts that the ratio of an electromagnetic to an electrostatic unit of

THREE-COLOR PHOTOGRAPHY

642

current represents a size equal to the dimension of velocity and that the
value of this velocity equals that of the transmission of light. Maxwell
demonstrated by his mathematical theory of electromagnetic phenom-
ena, following the ideas of Faraday, that the above-mentioned ratio
represents the velocity with which an electromagnetic disturbance
must extend in free space. This theoretical result formed the foundation
for his electromagnetic light theory, in which light is considered as a
periodical electromagnetic process. The investigations of Hertz, 11 in
the first place, the actual production of rapid electromagnetic vibra-
tions, and the experimental demonstration of their wave-like spread
with.a velocity equal to that of light, and, furthermore, the subsequent
tests, which showed that the behavior of light and that of electro-
magnetic waves are the same in every respect, have proved the Faraday-
Maxwell theoretical results so convincingly that no doubt of their cor-
rectness is possible. Maxwell’s fundamental work, Treatise on Elec-
tricity and Magnetism, was published in 1873. His electromagnetic
theory is now being used, especially in the mathematical formula given
it by Heaviside 12 and Heinrich Hertz. 13 This theory revived also
those early electric light theories, for which probably Grotthuss laid
the first foundation.

Henry Collen, teacher of painting to Queen Victoria, proposed in
1 863 a method for the production of three-color plates; he recommend-
ed making three negatives in “Brewster’s primary colors” (red, yellow,
and blue light) from these color diapositives, which he would super-
impose one on the other. 14

Baron Ransonnet, of Vienna, in the same year, also conceived the idea
of producing three-color prints with the three primary colors photo-
graphically, 15 but was discouraged from further experiment by the
lack of color-sensitivity in collodion plates. He does not seem to have
gone beyond the idea of manual photolithographic three-color print-
ing, 16 which he executed in some printed proofs. He also employed
a graytone plate (key plate), thus accomplishing a four-color result.

LOUIS DUCOS DU HAURON ( I 868)

Two Frenchmen, Louis Ducos du Hauron and Charles Cros, inde-
pendently of each other and without either one knowing anything of
the other’s work, outlined, in 1868 and 1869, the idea of reproducing
objects in their natural colors by the superimposition of three photo-
graphically produced pictures (blue, yellow, and red). Their work

THREE-COLOR PHOTOGRAPHY 643

greatly promoted the possibilities of practical results in this field. Du
Hauron’s idea consisted in making three diapositives in the primary
colors and combining these part-pictures in a peep box, where the
polychrome effect could be seen.

He presented a written and illustrated statement through Lelut, a
member of the Paris Academy of Sciences, but the Academy did not
include this statement in its reports. Many years later, in 1 897, this
historically important document of Du Hauron was printed and pub-
lished (E. J. Wall, History of Three-ColorPhotography, 1925, p. 104).

Not until 1865 did Du Hauron turn to practical photographic ex-
periments; he worked with silver bromide collodion and colored light
filters, producing three-color pictures with red, yellow, and blue
colored pigment diapositives. He achieved his first satisfactory proofs
in 1 868, when he applied for a French “privilege,” November 2 3, 1 868,
under the title “Les Couleurs en photographie, solution du probleme,”
and announced it on May 7, 1869, to the French Society of Photog-
raphy. Incidentally, Charles Cros, in the same year, independently re-
ported on his own work on the same principles of three-color print-
ing. At that time Du Hauron wrote several articles on his method of
three-color photography, which are reported in the Bulletin de la
Societe franpaise de photographie and Photographische Korrespon-
denz. These articles on the first work of Du Hauron are collected in his
Les Couleurs en photographie (Paris, 1869).

Later publications of Du Hauron were written partly in collaboration
with his brother Alcide, such as Traite pratique de photographie des
couleurs (Paris, 1878). They refer there to Vogel’s discovery of color
sensitizers during exposure of the separation negatives. Other publi-
cations by the brothers Du Hauron are: Alcide Ducos du Hauron,
Les Couleurs en photographie et en particulier Vheliochromie au char-
bon (Paris, 1870); Photographie des couleurs ( Algier , 1891); and La
Triplicite photographique des couleurs et I'imprimerie (Paris, 1897);
Louis Ducos du Hauron, La Photographie indirecte des couleurs (Paris,
1900).

Du Hauron’s influence on the progress of three-color photography
was important; he made the first successful experiments in photographic
three-color printing and exhibited his work at the Paris Photographic
Society May 7, 1869. It was stated: “The picture of the spectrum pre-
sented as proof is certainly far from perfect, nevertheless it substantiates
his statements.” Du Hauron, in his experiments, made three negatives

644 THREE-COLOR PHOTOGRAPHY

by the method now generally known, behind blue, green, and orange
colored light filters; after that, monochrome complementary red, yel-
low, and blue pigment prints were made and combined by super-
imposition to the polychrome picture. This is analogous to the modern
three-color printing which has grown so mightily. In 1 869 Du Hauron
announced a practical and perfect photochromoscope with three-
color diapositives, which projected the picture by means of lenses and
mirrors on the retina of the eye and formed additive color effects. In
the same year he also outlined the projection of pictures in colors by
throwing three-color diapositives in the primary colors on a white
screen by means of a triple projection lantern and uniting them in
one polychrome picture.

In 1869 Ducos du Hauron wrote in his work Les Couleurs en pho-
tographic (p. 54) that the synthesis of the three-color separations
could be changed by the use of a stereoscope, which would permit on
one hand the red and yellow separation to reach the eye additively,
while the third (blue) separation reached it through the second lens
of the stereoscope. The physiology of the human eye would render
it possible then to unite all three colors, forming a polychrome picture.
This idea did not prove successful in practice and was soon abandoned.
But this in no way deterred later inventors from reconsidering it.

Du Hauron also experimented in 1869 with the bleaching process
of producing color pictures. He wrote:

We must find a substance which has the property of undergoing a modi-
fication by the influence of light, which is analogous to that of the simple
and composite rays acting upon it, that is, a substance which will turn red
when exposed to red light, green when exposed to green light, and under
the action of white light turns white. 17

He then cites the work of Becquerel, Niepce de Saint-Victor, and
Poitevin and states:

Instead of causing the sun to create colors, could it not be employed for
the diffusion of color? Instead of searching for a simple preparation
which in some way absorbs and holds fast, on every point of its surface,
the color rays acting upon it, could we not subject to the action of light
a combined and polychromatically prepared surface? Or at least a sub-
stance which, as far as possible, contains all shades of color and which is
composed exclusively of already known and commercially produced
colors, spread equally over all points of the photogenic surface, so that
beneath each of the simple or composite rays acting upon it, the corres-

THREE-COLOR PHOTOGRAPHY 645

ponding simple or composite color will become fixed, while the other
colors would be eliminated by the action of the same rays? In this idea is
found the basis for the later production of pictures by the so-called
“bleaching process.”

It must be emphasized that Du Hauron was the first to describe
the screen color-plate process. He also pointed out the necessity of
adjusting the screen by such an arrangement of color elements that it
would appear gray and show no excess of any color whatsoever. He
states in his French patent specification of 1869 (No. 83,061): “We
imagine the whole surface of a piece of paper covered alternately
with extremely fine lines of red, yellow, and blue of equal size, with
no space between them; when viewed at close range the three-color
system of the lines can be distinguished, but seen from a distance they
merge into a single color tone, which, when viewed by looking
through a transparent medium, will appear white, but when viewed on
an opaque background will show gray if none of the three colors pre-
dominates.”

In 1874 Du Hauron made use for his three-color process of the
color sensitizing discovered by H. W. Vogel. 18 Before Vogel’s dis-
covery of color sensitizing for the visually bright color rays, three-
color photography could not be carried out successfully in practice.
After the publication of Vogel’s discovery, Du Hauron applied this
knowledge by sensitizing his silver bromide collodion plate with
Vogel’s coralline for green and with chlorophyll, as recommended by
Becquerel, for red. 18

Du Hauron also invented a three-color camera, in which the three-
color separations could be made simultaneously by a single exposure
behind complementary light filters. He was granted a French patent
(December 15, 1874, no. 105,881) for a “camera heliochromatique”
or a “photographic apparatus for the purpose of taking at one time
three pictures from one and the same object.” He writes:

1. We obtain by the aid of the photographic camera three negatives
of the same object, the first negative through a green colored glass, the
second negative through a violet colored glass, and the third negative
through orange-red glass.

2. Then transparent positives are made by the pigment or a similar proc-
ess by the aid of chromolithography, Woodbury type, or by a toning
process. From the first negative a red print is made, from the second a
yellow print and from the third a blue print. When the three mono-

646 THREE-COLOR PHOTOGRAPHY

chromes are superimposed and thus combined, we obtain a finished print,
which is a polychrome reproduction of nature. . . . [[Du Hauron at that
time knew only coralline as green and chlorophyll as red-sensitizers.]

Supposing that better sensitizers are found, it will then be desirable to
construct an apparatus with which the three pictures simultaneously and
without the interference of perspective can be photographed.

In order to obtain this result I have considered the following arrange-
ment, in order to photograph an object geometrically correct with a
single exposure.

The light rays coming from the subject to be reproduced are received
on a clear glass with parallel planes inclined at approximately 45 degrees
and are partially reflected towards the first lens. The greater part of these
rays penetrate the first glass and are received by a second clear glass, with
parallel planes also inclined at 45 degrees, and these light rays coming
from the same object are here further split up, and a part is here reflected
towards a second lens. The remaining light ravs penetrate through this
second glass and are collected directly by a third lens or by means of re-
flection from a glass or metal mirror . . .

In general, this description of a heliochromatic camera with two or
more reflectors agrees with the requirements demanded today. 19 Al-
most all Ives’s chromoscope cameras depend on the above basic sugges-
tions.

Blanquart-Evrard, of Lille, wanted to exploit Du Hauron’s process
and establish, in 1870, a three-color printing establishment. Du Hauron
had already furnished a set of three-color negatives for this purpose,
but, alas, the Franco-German war forced the postponement of the
project until 1871. Unfortunately, Blanquart-Evrard died in April,
1872, but he had reported the process to the Society of Sciences at Lille.
Du Hauron now confined himself, during 1 87 3, to the use of his process
for photolithography and showed portions of a color transparency.
He founded a company in 1 876 for the production of three-color prints
by photoglypty (Woodbury type), but it was extremely difficult to
register the three separations by this process, although he exhibited a
dozen such color impressions at the Paris Exposition of 1878. His
brother Alcide happened to be in Paris when the inventor of the power
press collotype process, Josef Albert, of Munich, visited the exposition.
Albert proposed to combine their work for Germany and France,
calling attention to his own success with three-color collotype prints,
which he had produced since 1874. Du Hauron declined the offer
and joined Guisac-Andre, who had a collotype plant in Toulouse.
Later he often exhibited three-color prints.

THREE-COLOR PHOTOGRAPHY 647

From 1874 Du Hauron made use of Vogel’s invention of color
sensitizers. 20 By the addition of dyes to silver bromide collodion he
obtained practical three-color separation negatives, the results of which
he exhibited at the Paris Exposition of 1878, and again in 1892 and
1894 at the exhibition of books. His brother Alcide was appointed a
court official in Algiers, and Louis lived there also from 1 884 to 1 896. 21

Josef Albert, at Munich, had long before this (1874) produced
good three-color collotypes, working with the then generally known
principles of the process and using Vogel’s color sensitizers. He began
his work with a collotype hand press and continued in this manner
until 1877 (Husnik, Phot. Korr., 1879, p. 1).

The first color collotypes of Josef Albert, made in 1874, were a
sample of a striped carpet, which was printed in the order of yellow,
blue, and red; and a reproduction of a picture in colors by Frik, of
Munich, showing a child of the Empress Frederick, to whom Josef
Albert presented them in 1 879. These, with an autograph on the reverse
side, are preserved in the Phot. Lehranstalt des Lette-Hauses, Berlin.

At the Graphische Lehr- und Versuchsanstalt, Vienna, and in other
places examples of Josef Albert’s color collotypes may be seen; they
were also published as inserts in the Photograpbische Korrespondenz,
Vienna, and in the Photograpbische Mitteilungen, Berlin.

Three-color collotype printing was carried on at Vienna by the firms
J. Lowy, Max Jaffe, at the Government Printing Office, and at the
Graphische Lehr- und Versuchsanstalt; also in Berlin and by the
experimental staff of the Imperial Printing Office at St. Petersburg.
For later developments see K. Albert, Lexicon der graphischen T ech-
niker (1927).

Du Hauron announced in 1 897 a process for the production of three-
color negatives by means of three plates or films placed one behind
the other and in one single exposure. On top he placed (glass side
toward the lens) a perfectly transparent ordinary gelatine blue sensi-
tive silver bromide plate (Lippmann emulsion), then a thin film sen-
sitive to green, then a red filter, and finally an emulsion sensitized for
red; thus he obtained with one exposure the separations for the yellow,
red, and blue plates. 22 This superimposition of three-color films, one
behind the other, was later called “tripack.” This early method was
recognized as worthy of attention and further elaborated by employing
thin films by the so-called “tripack process” by the English Colour
Snapshot Co., Ltd., and used for additive color projection (F. J.
Tritton, Phot. Jour., 1929, p. 362).

6 4 8 THREE-COLOR PHOTOGRAPHY

Du Hauron placed the so-called “anaglyphic process” on the market
at Paris ( Jahrb ., 1895, p. 404). Dr. du Bois-Reymond wrote in regard
to this (Phot. Rund., 1894, p. 199) that in 1853 W. Rollmann de-
scribed in Poggendorff’s Annal. (XC, 186) exactly the same process,
although for drawings only. Rollmann also laid out the pictures around
a common center, while Du Hauron shifted them a little. J. C.
d’ Almeida, at Paris, also published, in 1858, his method of projecting
stereoscopic pictures. He placed in his magic lantern a red and green
glass and projected with each a steroscopic view; the audience put on
spectacles of red and green glass in order to see the picture stereo-
scopically. 23

Du Hauron wrote several basic works on color photography: Les
Couleurs en photo graphie (1869); L'Heliochromie (1875); Traite
pratique de photo graphie des couleurs (1878). Compare further
Eugene Dumoulin, Les Couleurs reproduites en photographie (1876).
In his last work, Photographie indirecte des couleurs (Paris, 1900),
with his portrait, he collected his practical experiences with three-color
photography, and on page 44 of this book he gives proof of his rights
to the patents which he was granted.

Louis Ducos du Hauron derived no material benefits from his in-
ventions, and his old age was not free from care. The French govern-
ment awarded him the modest pension of 1,200 francs annually (at
that time about $240) in appreciation of his services. Thus was the
scholar and scientist rewarded. The Vienna Photographic Society pre-
sented Du Hauron, in December, 1904, with a gift. 24

CHARLES CROS

Charles Cros (1842-88) was a very versatile, ingenious man, who
at one time devoted .himself to mechanics with the talking machine
and photography and at another time became prominent as poet and
painter.

It is curious that he, at the same time as Du Hauron and absolutely
independently, worked on three-color photography. On December
2, 1867, he presented to the French Academy of Sciences a sealed
package, containing a report of his experiments, which had as their
object the production of the three separation negatives and their
synthesis for three-color photography. 25 He kept his process secret,
however, until it became known that Du Hauron had patented his

THREE-COLOR PHOTOGRAPHY 649

three-color process on November 23, 1868. It was only after Du
Hauron published the first of a series of articles in the journal Le Gers
(March, 1869) on this same subject of three-color photography that
Cros was induced to make his findings public.

On February 25, 1869, Cros published in the French journal Les
Mondes an article on the solution of the problem of photography in
colors, (entitled “Solution du probleme de la photographic des
couleurs”), which also appeared as a pamphlet. He accepted red, yel-
low, and blue as the primary colors and started from three comple-
mentary negatives. For their production Cros used light filters of
colored glass or liquid filters, just as in the later usual method. He also
mentioned the illumination of objects by colored lights during ex-
posure. He also proposed another way— by projecting red, yellow,
or blue light into the camera by prisms— and described clearly and in
detail the “prismatic dispersion process.” Cros in this anticipated the
dispersion processes of Wordsworth Donisthorpe (1875) and K. J.
Drac (1904, 1906). For the color synthesis of these negatives Cros
emphasized the additive method of observation, along the lines of the
chromoscope; but he also mentioned the viewing in the phenakisto-
scope or zoetrope.

Cros described in 1879 and exhibited before the Paris Photographic
Society an apparatus which he called “chromometer,” which con-
tained orange-red, green, and blue-violet light filters and composed
the complementary diapositives with the aid of transparent plate
glasses in the eye of the observer. [A diagram of his chromometer
is reproduced in the 1932 German edition of this History (p. 94OT
This was the basis of later photochromoscopes of Ives and others.

On this basis Charles Cros constructed a camera for three-color
photography, which his brother A. H. Cros patented in 1 889 in France
and England. Cros is also the inventor of the production of color pic-
tures by the “Absauge” method. He coated a glass plate with bichro-
mated gelatine, exposed under a glass diapositive, washed with water,
and soaked the coating with suitable dye solutions, which were absorbed
only in the nonexposed parts. Thus he obtained diapositives in color,
which he called “hydrotypes” ( Moniteur de la phot., 1881, p. 67).
This was the basis for a method by Selle (Phot. Korr., 1896, pp. 192,
294, 442 ) and the “pinatypy,” by L. Didier in Xerligny, France, which
was further elaborated by Dr. E. Konig of the Hochst Dye Works

6 5 o THREE-COLOR PHOTOGRAPHY

in 1905 (German patent, no. 176,693; see also Handbuc h, 1926,^(2),

377 )-

Charles Cros studied medicine and philology. He was both a scien-
tist and a poet; also a member of the “College Libre de Medicine,”
Paris. Cros worked on the invention of an autographic telegraph
instrument (1867), a phonograph (1879), wrote on the means of
communication with the planets by optical telegraphy (1869) and
also a medical work on the mechanics of the brain (1880).

Personal communications by M. Potonniee to this author call atten-
tion to a collective description of Cros’s scientific plans in Cros’s book
Le Collier de griffes, which appeared under the pen name “Emile
Gauthier.” It contains the statement that Cros was making investiga-
tions into the synthesis of precious gems, the radiometer, and the
photophone. He also occupied himself with electricity, musical stenog-
raphy, which was realized by others under the name “melotrope,”
and also with the autographic industry (Potonniee).

Cros’s poetical works are, according to M. Potonniee, as follows:
Le Coffret de santal (Paris, 1873; 2d ed., 1902); Le Fleuve (Paris,
1874); and Le Collier de griffes (Paris, 1908). The last-mentioned was
published after his death by his son Guy Charles Cros.

In 1874 Cros published Revue du monde nouveau, of which only
three numbers appeared. For the history of photography his work,
Solution generale du probleme de la photo graphie des couleurs (Paris,
1869) is particularly valuable. Note sur /’ action des differentes lu-
mieres colorees sur une couche de bromure d'argent impregne de
diver ses matieres color antes organiques (Paris, 1879) we shall refer
to more in detail later in this book.

Cros delivered his first lecture on color photography before the
French Society of Photography, Paris, May 7, 1869; all his articles re-
ferring to photography are printed in the bulletin of this society. They
are also extensively published in the Pbotogr aphis che Korrespondenz,
edited by E. Hornig.

With respect to the role Cros plays in the history of photography,
it is of interest to consider his part in the invention df the phonograph.
France contested the priority rights of Edison, who was everywhere
called the inventor of the phonograph (1877), in favor of Cros. The
Academy of Sciences in Paris celebrated the jubilee of the invention
by Cros in April, 1877, while the Americans exalted Edison as the
real inventor on August 10, 1927. The New York correspondent of

THREE-COLOR PHOTOGRAPHY 651

the Paris Matin interviewed the great inventor Edison, who stated:

The phonograph was fifty years old on August 10, 1927. On this date,
fifty years ago, I ordered one of my mechanics to construct the first ap-
paratus according to my specifications. It took thirty hours to do this. In
the forenoon of August 12, 1887, the voice of a phonograph was heard
for the first time in my laboratory. The apparatus was then already so
perfect, that it differed only in quite unessential details from the general
tvpe of phonograph as it is used today.

“How do you explain the fact,” asked the reporter, “that the French
physicist, Charles Cros, who then claimed the authorship of the in-
vention, is today still considered in France the real inventor of the
talking machine?”

It is certain [^replied Edison] that in July 1877, I conceived the idea oi
constructing a talking machine, as I said before, I ordered the first ap-
paratus built on August 10, 1877. Cros, probably without question, trans-
mitted somewhat earlier, that is, on July 30th of the same year, a sealed
envelope with the plan of his phonograph to the Academy of Sciences,
at Paris, but the envelope was not opened until December 3, that is, at a
time when my machine had been in use for a long time. A comparison of
his plan with my apparatus demonstrated that Cros had in mind an en-
tirely different manner of the realization of a talking machine. At any
rate, his plan was never executed up to the present time. Whatever may
be thought of the paternity of the idea for a talking machine, the fact re-
mains that the first machine which really talked was my work, and this
ought to decide the contention finally! There is no doubt, of course, that
Charles Cros had a great and original mind; he thought and found the
correct solutions in many other technical fields, but unfortunately he al-
ways lagged in their execution. Thus he gave an important impetus to
color photography by his statements, which others took hold of, realized
and made money out of. This tardiness was in a certain measure his
tragedy. He was inconsistent, sought immortality at one time as poet and
at other times strove for the painter’s laurels, and thus he lacked that
peculiar ability of concentration and inner composure, without which
nothing great and permanent can be created.

In the history of three-color photography Louis Ducos du Hauron
and Charles Cros must be put in the first place side by side. At the
session of the Paris Photographic Society on May 7, 1869, Davanne
verified the fact that both inventors, at the same time and independently
of each other, worked on the same subject. 20 Cros made his experi-
ments in the studio of a rich amateur, the Duke of Chaulnes. The

6 5 2 THREE-COLOR PHOTOGRAPHY

famous Paris collotyper Dujardin occupied himself (1878) with mak-
ing collotype printing plates for the reproduction of Cros’s negatives
from colored objects. 27 Du Hauron knew only the method of using
three-colored glass plates for negatives, while Cros had already con-
sidered the production of three-color negatives by means of mono-
chromatic illumination of the originals during exposure. 28 Du Hauron,
on the other hand, as Davanne stated, had presented to the Paris Photo-
graphic Society on May 7, 1 869, the first more or less successful, and
in fact practical, three-color photographs (colored spectrum, see earlier
in this Chapter) and by this had won precedence over Cros.

In the meantime the above-mentioned publications by Du Hauron
appeared and at the end of the seventies Cros 20 published studies on the
classification of colors and the means by which all shades could be
reproduced by three negatives (red, yellow, and blue). Cros wrote:
I have been busy for some time trying to find photographic films which
are sensitive to rays of all colors, especially to orange-red, green, and
violet. In order to obtain these ravs, I use transparent troughs (cells) filled
with salt solutions, which filter the composite light.

Du Hauron carried on three-color printing more persistently than
Cros, and his numerous publications were especially stimulating and
advancing. In the British Journal of Photography (1906, p. 7) the
patents of Du Hauron and Cros are published chronologically and
with illustrations.

The real progress of three-color printing came only with the dis-
covery of optical sensiti'/.ers by Vogel. Du Hauron dyed his plates
according to Vogel’s method and announced on September 6, 1875,
to the Society of Agriculture, Sciences and Arts, Agen, that he used
chlorophyll, the sensitizing effect of which for the red end of the
spectrum was discovered by Edmond Becquerel. The silver bromide
plates can be sensitized with dyes, however, for red, yellow, and green,
which Vogel pointed out.

Du Hauron continued his experiments with color-sensitive plates
and announced in i 878 : ‘° that all photographic processes could be
adapted to three-color printing. “We can choose,” Du Hauron states,
“between the pigment process, Woodbury type, collotype, the dusting-
in process, or the silver chloride method, with the use of suitable toning
baths, etc.” He preferred at the time the pigment process with three
colors, namely, carmine, prussian blue, and chrome yellow, although
he had great difficulty in registering the prints. Du Hauron made not

THREE-COLOR PHOTOGRAPHY 653

only three-color pigment prints o n paper but also polychrome pictures
on glass, windows, and so forth. 31 He anticipated the principles under-
lying practically all varieties of three-color prints, which appeared
with the later improvement of the reproduction processes by many
inventors and experimenters.

The brothers Alcide and Louis Ducos du Hauron gave the fruits of
their experience in their Traite pratique de photograpbie des couleurs
(Paris, 1878), 32 in which they used the orthochromatic collodion proc-
ess for making their negatives behind green and orange filters and
introduced eosin collodion. At the First International Exhibition for
Color Photography, at Paris, in 1904, such three-color photographs by
Du Hauron, of the seventies, taken partly from nature, were shown. 33

Leon Vidal, of Paris, also worked successfully with the production
of three-color pigment pictures during the seventies of the last century.
He was the first to produce color combination prints of chromolitho-
graphs with a brown pigment picture, especially he combined chro-
molithographs with a black Woodburytype printed last, which gave,
owing to its transparency, excellent fine effects in reproductions of
the work of goldsmiths (set with jewels) on a gold bronze background.
The technique, which has been entirely discontinued, owing to the
difficulty in reproduction, is unexcelled for this purpose. 34

In the eighties Angerer and Goschl, at Vienna, as well as Goupil,
of Paris (now Boussod & Valadon), produced four- and five-color
zincographs, without achieving very much color separation in a purely
photographic manner; good color prints were obtained, but only by
the aid of a great deal of retouching by hand.

Photographic three-color printing attained a new impulse from the
energetic invention of Vogel in 1891, especially after he devoted him-
self with all his zeal to the reproduction side of three-color printing.

Vogel had broadened, in 188 5, 35 the theory of three-color printing.
Emil Ulrich, a Berlin lithographer, experimented in 1 890 with color
collotype following these principles 38 and exhibited proofs at the
Photographic Congress of Berlin (1890), as well as to the Society for
the Advancement of Photography; he printed a fourth collotype plate
in black as a key plate. He joined Ernst V ogel, the son of H. W. V ogel,
in order to exploit this “four-color collotype printing,” and the firm
of William Kurtz, New York, offered to buy the process and adapt
it for halftone relief printing, which seemed much more practical for
book illustrations than the collotype process.

6 5 4 THREE-COLOR PHOTOGRAPHY

Ernst Vogel tried out different color filters and systems in Berlin
and then went to New York, where he and Kurtz, employing azaline
plates, made the first artistic and really satisfactory three-color prints,
in 1892. They published a three-color halftone in the January, 1893,
number of the Photograpbische Mitteilungen (signed E. Vogel-Kurtz) .
The firm Buxenstein, at Berlin, took up later the production and print-
ing of three-color process plates on the advice of E. Vogel.

In the meantime Eugen Albert, at Munich, had also taken up the
three-color process with Levy screens. He took out a German patent
(No. 64,806) on May 9, 1901, for halftones and photolithographs in two
and more colors. He patented the turning of the screen during ex-
posure behind red, green, and blue violet light filters, at an angle of
to degrees, in order to avoid a pattern (moiree) when the yellow,
red, and blue impressions of the plates were printed on top of each
other. 37 Buxenstein acquired this patent later, but it was not sustained
and therefore did not interfere with the progress of reproduction tech-
nique.

Others who worked at three- and four-color processes intensively
were Angerer & Goschl, Vienna; Husnik and Vilim, Prague; Meisen-
bach and Riffarth, Berlin, and many other men and establishments.

THREE-COLOR COLLOTYPE

It is worthy of notice that the English officer James Waterhouse
was the first to employ three-color photography, in 1 894, in Calcutta,
assisted by A. W. Turner, a collotyper there. He printed collotype
intaglio plates in order to obtain reproductions in natural colors by
red, yellow, and blue inks, which he also applied to printing maps in
colors ( Jahrbuch , 1895).

Three-color collotype printing gives very pleasing effects. Artistic
reproductions of oil paintings in large sizes were 38 probably first made
by this method in 1904, at the Graphische Lehr- und Versuchsanstalt,
Vienna, under the direction of Professor G. Brandlmeyer.

VARIOUS THREE-COLOR PHOTOGRAPHIC PRINTING PROCESSES

The production of polychrome pictures by photographic printing
processes based on the subtractive three-color method was successfully
accomplished. Both gum printing (repeated sur-printing of yellow,
red, and blue films) and pigment printing were employed. In the
latter case three films, yellow, red, and blue, either pigment tissues

THREE-COLOR PHOTOGRAPHY 655

or chromated gelatine prints tinted by immersion in dye solution
(hydrotype of Cros), were superimposed. We mention, for example,
here the work of G. Selle 30 and that of the brothers Lumiere ( Hand -
buck, 1926, Vol. IV), as well as that of Krayn (Neue Photographische
Gesellschaft, Berlin). The pinatype method was and still is largely
employed in the production of three-color pictures, both for diaposi-
tives and for paper prints. For the production of tanned gelatine films,
which, impregnated in dye solutions, are absorbed by gelatine or col-
lodion paper pressed against them, not only the pinatype method is
adaptable, but also the so-called “Jos-Pe” method of Koppmann (1925)
with tanned prints and pyrocatechin development ( Handbuch , 1926,
IV ( 2 ) , 402 ) and several newer processes.

Here belongs also the kodachrome process (not to be mistaken for
kodacolor) of the Eastman Kodak Company, which is based on mor-
dant dye processes, as well as the excellent diapositive method “uva-
chromy,” of A. Traube, which was also successfully used for poly-
chrome paper prints (uvatypes) (see also Namias in ch. lxxv, and
Handbuch, 1926, Vol. IV, Part 2).

The ordinary photoprinting methods used for making blue prints,
also color toning of silver prints in baths for blue, yellow (lead in-
tensification and subsequent chromium baths), and orange-red (toning
with uranium and mordant dyes), were employed for these subtractive
color prints. To enumerate them all would take too long, and we cite
only one simple example: A. Gurtner produced color prints with the
two-color system (orange and blue), using for it the usual toning
methods for silver prints, namely, toning the blue in a ferricyanide-
iron chloride bath and by making an untoned strippable print on cel-
loidin paper, which is a brick-red color and is superimposed on the
blue component of the picture (German patents, 1902, Nos. 146,149
and 1 46, 1 50 ) . These and numerous other such methods are described in
Wall’s History of Three-Color Photography (1925, p. 155), and all
kinds of color toning methods appertaining to this in the issues of Eder’s
Jahrbuch.

COMBINATION OF COLOR PROCESSES

In many cases various photomechanical or other printing processes
were combined. For very large editions (picture postcards and such)
color lithography or color woodcuts were used with the halftone
process. For art subjects, color lithography, algraphy, photogravure,

THREE-COLOR PHOTOGRAPHY

656

and collotype were employed in various combinations. The first im-
petus in this direction was probably given by prints made by a com-
bination of color lithography and collotype by H. Ecker and A. K.
Koppe, at Prague, in 1873. Otto Troitzsch and E. Gaillard, at Berlin,
were very successful in 1877 with this combination printing, which
had been used only in an experimental manner by the firm at Prague.
They called it “heliochromy” (also “Troitzschotypie”). This com-
bination of several printing methods was subsequently often employed.
Among others, good prints of this sort were made by J. Lowy, Vienna,
by Meissner & Buch, Leipzig, and by the Government Printing Office,
Vienna, which cultivated especially the combination of chromolith-
ography (six or more plates), and later algraphy with collotype or
with photogravure. A great advance over these earlier methods is
shown by the art prints which Professor Brandlmeyer produced in
1897, at the Graphische Lehr- und Versuchsanstalt, which combined
for the first time pure three-color collotype with photogravure and
later three-color lithographic algraphy with photogravure.

THREE-COLOR PROJECTION

Prompted by Maxwell’s suggestion of color projection, Du Hauron
studied and described in his Les Couleurs enphotograpbie (Paris, 1869)
the principle of three-color projection, but he never demonstrated
his theory in practice. Leon Vidal elaborates on this in the author’s
Jahrbuch (1893, pp. 4, 302). It may be said without in any way di-
minishing the rights of later inventors that all the different experiments
of this kind can be traced back to the basic ideas of Maxwell, Du
Hauron, and Cros.

The first practical and successful color projection of three dia-
positives on a screen seems to have been made by the American
Frederic Eugene Ives. He projected at Philadelphia, in 1888, such
three-color pictures by means of a triple projection lantern and three
different diapositives, backed with red, green, and violet glass. This
public demonstration is reported in the Journal of the Franklin Institute
(1889, p. 58).

Ives patented his method in America on February 7, 1890, (No.
432,530), describing it as a projection of three diapositives, made
behind red, green, and violet filters to the same spot on a white wall
in register, on top of one another by means of a triple projection
lantern illuminated with red, green, and blue-violet light. Ives called

THREE-COLOR PHOTOGRAPHY 6 57

his apparatus a “triple projection lantern” and with it he was the first
to achieve satisfactory results from this method.

Leon Vidal, at Paris, also carried out the same ideas and presented
(similar to Ives) colored projections with three separately function-
ing projection lanterns, with three-color diapositives and colored
illumination, on February 7, 1892, at a lecture before the “Conserva-
toire Nationale des Arts et Metiers,” where he was professor of photog-
raphy. He repeated this illustrated lecture on March 4, 1892, before
the Paris Photographic Society. He sent his pictures to Vienna, where
E. Valenta showed them in the projection room of the Society for the
Propagation of Knowledge in Natural Sciences. Vidal’s lectures caused
the optician C. Nachet, in Paris, to construct a “stereo-photochromo-
scope” in 1894.

Professor A. Miethe, in Berlin, used, in 1903, the same idea as Ives
and Vidal for the additive color projection of three-color positives,
which had been made with the use of his panchromatic ethyl-red plates
from nature. The apparatus used by Miethe was constructed by the
Goerz Optical Works. This apparatus differed very little from Ives’s
“triple lantern”; in the Miethe-Goerz apparatus the lanterns were
placed one above the other instead of side by side. Miethe inserted red,
green, and blue-violet liquid filters in glass cells, which contributed
a cooling effect in the path of the rays from the electric projection
lamps. With this apparatus colored pictures by additive synthesis were
shown on large projection screens at Berlin in 1903. The negatives
from nature were made with a camera provided with a long strip of an
ethyl-red plate enclosed in a falling plate holder which moved the
negatives downward in rapid succession, while a pneumatic shutter
made very short exposures possible. This camera (“Miethe-Bermpohl-
Kamera”) was built by Bermpohl, Berlin, in 1902.

For the purpose of making the rapidly successive exposures of the
separation negatives for the three-color process, especially constructed
motion picture cameras were also employed. B. J. Mroz, at Vienna,
patented in 1 92 2 a three-color pocket camera for use with panchro-
matic motion picture films. The simple movement of a lever opened
the lens shutter, moved the strip of film, inserted the colored light
filter, so that in the space of four seconds the three separations,
properly divided, were obtained ( Jahrbuch , XXX, 144).

Many different kinds of cameras for making three-color negatives
were constructed; most of them sought to attain a simultaneous ex-

658 THREE-COLOR PHOTOGRAPHY

posure of the subject to be photographed. The important point was
the necessity of avoiding parallax. Many types of construction used
the method, laid down by Du Hauron, of using reflecting plate glass
vhich reflected the light in part, but permitted it to penetrate some-
vhat, and thus produced in this manner three-color separations behind
ied, green, and blue filters. Ives called this kind of camera “chromo-
scope” and later also “photochromoscope cameras.”

These types of construction were essentially the same as Du Hauron’s
camera. Du Hauron, however, described them only for use in making
subtractive three-color photographs. Ives specified his camera also for
additive three-color synthesis, and was the first to achieve practical
results.

Ives’s first English patent on three-color cameras is that of 1892
(No. 4,606); later he took out various other patents in 1895 and 1899
on similar types of construction. Concerning the controversy of Ives
vs. Pfenninger relative to these patents see British Journal of Photog-
raphy (1907, p. 54, and 1914, p. 61).

Later followed British patents by Edwards (1895, No. 3,613) and by
White ( 1 896, No. 8,663). In the British Journal of Photography (1906,
p. 178) the further course of these inventions and patents by other
scientists (Bennetto, Butler, etc.) was published.

Ives also made three-color projection serviceable for motion picture
photography in 1897 and recommended a projection lantern with
movable color filters. Then followed W. Friese-Greene, 1898; Turner,
1899; and others. J. Gaumont, at Paris, produced motion picture pro-
jectors for three-color pictures. In this system the film images were so
small that all three took up no more space than two ordinary film
pictures. These he projected additively by means of an ingenious
triple projection lens.

The history of motion picture projection in colors is described by
Otto Pfenninger ( Jahrbuch , 1910, p. 29) and exhaustively up to
present time by Wall, History of Three-Color Photography (1925).

Ives himself (1888) did not consider the practical method of three-
color projection by three projection lanterns as final. The necessary
projection lanterns, difficult and costly to procure, prevented the spread
of the art. He therefore continued his work in this field and con-
structed next a special camera for taking the three-color separations
(“chromoscope camera,” 1891). The usual diapositives made from
these separations were illuminated in a different novel arrangement

THREE-COLOR PHOTOGRAPHY

659

by appropriate red, green, and blue glasses, and were brought together
in a small diascope in ordinary daylight for optical superposition and
synthesis of the colors. They presented to the observer a reproduction
true to nature in light, shade and color. This apparatus, which Ives
called “heliochromoscope,” was equipped with reflecting plate glass
as mentioned above and was very original in its construction. Ives
described his “heliochromoscope” (or “photochromoscope”) in the
Journal of the Society of Arts of May 27, 1892 (also in the Jahrbuch,
1894, pp. 217, 457). He demonstrated it in London in the autumn of
1893 with great success. On December 18, 1894, Ives was granted an
American patent (No. 531,040) for his photochromoscope. One of
the first examples of his photochromoscope was presented by Ives to
this author, who demonstrated and described it in detail before the
Vienna Photographic Society (Phot. Korr., 1893).

Ives’s photochromoscope incited others to construct similar appa-
ratus. Karl Zink, of Gotha, constructed in 1 893 his “photopolychromo-
scope,” 40 which, however, is not so compendious as Ives’s apparatus,
and there were other attempts along the same lines.

TETRACHROMY

Tetrachromy for the production of color photographs is based on
the division of the spectrum into four color zones which border on each
other (red, yellow, green, and blue) . This system was first proposed
and described in detail in a lecture before the Society for the Pro-
pagation of Knowledge in the Natural Sciences in Vienna by the
author (V ereins-schriften of the Society, XXXVI, 235; Phot. Korr.,
1906, p. 231; Jahrbuch, 1907, p. 245). Ten years later, Zander applied in
England for a patent on exactly the same subject, thinking that he
had made a new invention. The patent was refused in Germany, be-
cause this author proved the lack of originality. At any rate, this tetra-
chromy which Zander attempted to introduce into the printing in-
dustry has no commercial advantages over the more simple and there-
fore more efficient three-color process, which makes this matter merely
of historical interest.

FOUR-COLOR PROJECTION

A. Scott sought to improve on Ives’s three-color projection by a
four-color projection (purple, yellow, green, blue) with a quadruple
projection lantern illuminated by a single light source, but he was
unable to obtain any superior results ( Jahrbuch , 1892, p. 433).

66 o

THREE-COLOR PHOTOGRAPHY

The Japanese Katsujro Kamei also invented a similar method of
four-color projection (English patent No. 143,597, February 19,
1919).

TWO-COLOR PROJECTION

For two-color projection bluish-green and orange-yellow light fil-
ters are employed, which by additive projection give an illusion of
true colors in photographs taken from nature. The first practical results
were exhibited by B. Jumeaux and W. W. L. Davidson at Paris, in
1904, and at the Photographic Convention at Southampton (England)
in 1906. Their English patent (No. 3,729) is dated 1903.

C. A. Smith constructed a two-color apparatus (“kinemacolor”)
with red and green sectors and opaque interval sectors. He was granted
an English patent (No. 26,671) in 1906, which was annulled in 1915.
His cinema color was presented for a time (1907 until about 1914)
quite frequently (see Liesegang, Wissenschctftliche Kinematograpbie,
1920, p. 167).

Bernard’s two-color films (additive system) was worked out by
the Raycol British Corporation, Ltd., according to the English patent,
No. 329,438 (Brit. Jour. Phot., November 7, 1930; Kinotechnik, 1930,
p. 625).

A typical two-color projection film by the subtractive method was
worked out by J. G. Capstaff in the research laboratories of the
Eastman Kodak Co. 41 The silver image for the red and green com-
ponents is produced on gelatine silver bromide films by means of the
mordant dye process, and these two-color images are photographed
on both front and back of the film in register. Similar methods were
announced by other inventors. On two-color printing from twofold
printing forms see Karl Albert, Lexikon der grapbischen T echniken
(1927, pp. 45, 270).

PHOTOCHROMY BY JUXTAPOSITION OF SMALL COLOR ELEMENTS—
COLOR SCREEN PROCESS

When small red, green, and blue color elements of pictures are
placed in juxtaposition and observed visually, they merge into a color
picture. This kind of additive color synthesis was considered by Du
Hauron as early as 1868, but was never carried out by him in practice.

Independent experiments of this kind were made by J. W.
McDonough in 1892, and he was granted in that year both an English
patent (No. 5,597) and American patents (Nos. 471,186 and 471,187)

THREE-COLOR PHOTOGRAPHY

66 1

on his invention. At first he employed color-screen plates with granu-
lar powder in the three primary colors. For this purpose he first
coated a glass plate with a sticky layer, on which he applied a mixture
of very small colored red, green, and blue particles, like resin or such.
On top of this color screen he flowed the emulsion, and the exposure
was made through the color film. The idea was a good one, but the
execution very difficult, and McDonough’s invention was not suc-
cessful in practice.

In the meantime the Englishman John Joly, of Dublin, had carried
on experiments with color screens which he produced with a rather
coarse line grating on glass, which consisted of red, green, and blue
lines 0.12 mm. wide next to each other. The color sensitized plate was
exposed behind this three-color line screen. The negative showed
naturally a color separation. The diapositives made from these negatives
were viewed through such a color screen and presented to the ob-
server a polychrome picture. The first English patent of Joly is dated
1893 (No. 7,743).

Notwithstanding their coarse lines, Joly’s color screen pictures
achieved a great success, and quite a large number of them were sold;
but it often became necessary to realign from time to time the photo-
graphic diapositive with the three-color line screen, which was incon-
venient and disagreeable. The screens of Joly, although merely tem-
porary, induced McDonough to drop his earlier grain screen method.
He turned to a screen similar to Joly’s, but used finer lines (British
patent, 1896, No. 12,645). We will discontinue the consideration of
the line color screen, because the grain screens have achieved now a
victorious precedence.

Here must also be mentioned the English patent No. 8,390 (German
patent No. 96,773) granted in 1896 to Brasseur and Sampolo, who
produced their color-screen plates with colored transparent celluloid
grain or other transparent substances. In some of his patents A. Bras-
seur mentioned the possibility of the use of such color films for motion
picture photography, but he was unable to introduce them into practice.

The first real and lasting success was achieved by the brothers A.
and L. Lumiere, of Lyons, in 1903, by their autochrome process. The
production on a large scale of autochrome plates was extraordinarily
expensive, which difficulty was not overcome until 1907, when they
succeeded in placing the first perfect and efficient plates of this kind
on the market. The autochrome plates carry on a glass plate mixed

662

THREE-COLOR PHOTOGRAPHY

red, green, and blue starch grains, on which a thin film of panchro-
matic gelatine emulsion is applied. The exposure takes place through
the glass and the color grain base.

Lumiere’s autochromes found general and permanent favor. Equal
to them are the German color screen plates made by “Agfa”; both
have been often described.

Colored diapositives were not considered as an end even at the time
of the first autochrome plates, and the idea was conceived to produce
with their aid color prints on paper. The most efficient way turned
out to be the making of separation negatives from autochrome dia-
positives, from which three-color process plates were made for typo-
graphic printing. 43

Autochromes were, of course, also used as color guides for collo-
types, uvachromes, and pinatypes in colors. Color proofs on paper
from autochromes were attempted by E. C. G. Caille (English patent,
1908, No. 15,050); similar attempts are published in the Jabrbuch
(1910, p. 387; 191 1, p. 371; 1912, p. 372; 1913, p. 301). The method
was not successful.

The color-screen method was also made to serve for projection in
color. Thus Dufay’s omnicolor plate was developed into the English
Spicer-Dufay color cinema film and successfully projected in the
summer of 1931 at London. They produced on a strip of film a red,
blue, and green mosaic light filter from a lineature, and by reversal,
turned the film negative into a positive which could be rapidly printed
and thus reproduced. Thorne Baker reported on this at the Photo-
graphic Congress of 1931 at Dresden (Brit. Jour. Phot., 1931, No.
3,790). The Agfa Company also exhibited narrow films with a three-
color screen system (reversible films) at that Congress, where J. Eggert
gave a demonstration of other noteworthy color film systems of the
time.

JAN SZEPANIK’s THREE-COLOR WEAVING

The Austrian Pole Jan Szepanik (1872-1926) was an amateur pho-
tographer who built his own cameras. In 1896 he attracted public
attention with his process of producing weave patterns for Jacquard
looms by photography. Baron Ludwig Kleinberg, a countryman of
Szepanik, backed him financially, and in 1 896 an Austrian patent was
granted them jointly for an “electric Jacquard machine” and for a
“process for the production of a pattern for electrically driven looms”

THREE-COLOR PHOTOGRAPHY 663

and finally for a “method and installation for the production of weave
patterns by photography.” Szepanik elaborated Joly’s color photog-
raphy with three-color line screens to such an extent that he was able
to weave pictures in natural colors. Two monochrome examples of
large size (the portrait of Emperor Francis Joseph) as well as a silk
gobelin, 148 X 120 cm. (about 4X5 ft.) were presented by the in-
ventor to this author and are preserved at the Graphische Lehr- und
Versuchsanstalt, Vienna.

An efficient designer, working by hand, would have required several
years for the production of the patterns for a silk gobelin, while
Szepanik’s machine will accomplish the work in a few hours. In order
to enable him to distort designs according to any requirement, Szepanik
used a Zeiss anamorphot equipment. In a subsequent patent he published
an arrangement for multiplying pictures with the aid of perforated
cards and peculiar diaphragms, which might also be emp’oyed in the
production of background and border designs for bonds, banknotes,
and certificates. The photographic weaving process did not meet with
general acceptance in practice; the establishment at Barmen (Ger-
many) was closed in 1902, and the Vienna factory, in 1903. Szepanik
invented, in 1902, an arrangement for the simultaneous exposure of
the color separation in three-color photography. 44 He also announced
at the same time a modification of Word’s bleaching process, in which
he worked with three superimposed bleaching layers. After auto-
chrome plates appeared commercially, Szepanik turned to screen plate
color photography and worked out a color screen after new principles,
which he later improved jointly with Dr. Hollborn, in Dresden, and
sold in the market for a short time as “veracolor plates.” During the
World War he returned to Galicia (Austria), where he made his last
invention, namely, an arrangement for motion pictures in natural
colors, of which a model was built by the Emil Busch Company,
Rathenow. This is described in detail in Photographische Industrie
(1925). Although Szepanik was unsuccessful commercially, his in-
ventions proved his genius and pointed out the road along which other
inventors could proceed with greater success. Szepanik’s numerous
works are described in detail in issues of the Jabrbuch, in Phot. Korr.
(1919, p. 331), and in Wall’s The History of Three-Color Photog-
raphy ( 1 92 5 ) . Poland acclaimed him as one of its greatest inventors,
hailed him as the “Polish Edison,” but his ingenious inventions have
thus far been only ephemeral.

PHOTOCHROMY

664

We have reported here only in rough outline the history of three-
color photography. The field has grown enormously by the advent
of color projection, motion picture photography, and other processes
with two or more colors. The most exhaustive work to date on the
historical development of these processes is E. J. Wall’s History of
Three-Color Photography (1925). E. Matthews published still later
developments in his article “Processes of Photography in Natural
Colors” in the Journal of the Society of Motion Picture Engineers of
America (1931, XVI, 188, 219). Also see Jahrbuch, Vols. XXXI-
XXXII.

Chapter XCV. photochromy; color pho-
tography WITH SILVER PHOTOCHLORIDE; LIPP-
MANN’S INTERFERENCE METHOD AND “PHOTO-
GRAPHIE INTEGRALE”; KODACOLOR; BLEACHING-
OUT PROCESS

The first indication of the origin of natural colors by the action
of light was given by Senebier in 1782, when he announced the obser-
vation that silver chloride took on in violet light more of a hue towards
blue, but lighter shades towards the other end of the spectrum.

But the physicist Seebeck, in Jena, was the first to determine, in
1810, exactly and in detail that the solar spectrum produces shades of
color on silver chloride paper similar to those colors of the spectrum
which strike it.

Sir John Herschel made further observations in this direction; he
observed in February, 1 840, that paper treated with silver chloride
and darkened in sunlight takes on, under the influence of the rays of
the spectrum, in red, green, and blue light, the analogous colors. These
experiences found as little appreciation, however, as those of Seebeck,
because the whole world was convinced of the impossibility of the
problem’s solution. The fact observed by Herschel was considered
a mere accident. 1

The results of the investigations of Edmond Becquerel on photo-
chromy (1847, 1848, and 1855) surpassed all those preceding them.
He prepared his sensitive film by polishing a silver plate and immersing

PHOTOCHROMY

665

it in a metal perchloride solution or in chlorine water; a violet film of
silver subchloride formed, which under the influence of colored glass
or of the spectrum takes on the impression received and which retains
this color photograph as long as subsequent light action is avoided.

Niepce de Saint- Victor devoted himself from 1851 to 18 66 to Bec-
querel’s method of heliochromy with chlorinated silver plates, inproved
the process, and obtained more brilliant and more vivid colors than
those of his predecessor . 2 When a blank polished silver plate is coated
by the action of chlorine with a thin coating of silver subchloride (silver
photochloride), it changes under the influence of the solar spectrum
in such a way that the affected parts show shades of color similar to
the color rays by which they were struck. The “chlorinating” of the
silver plate was made by different methods with various degrees of
success.

The silver plate was immersed in a solution of iron chloride or copper
chloride (Becquerel), a mixture of both, or in a warm solution of
potassium chloride with copper sulphate, washed after a few seconds
and dried; 3 or it was held over chlorine water until it showed a whitish
faintly pink color (Becquerel).

Becquerel preferred chlorination by the galvanic process. The silver
plate was immersed as the positive pole in weak hydrochloric acid
(1:8), the negative pole being a platinum sheet. Within the space of
a minute the silver plate takes on gradually a gray, yellowish, violet,
bluish color, which repeats itself in the same sequence; at the moment
before the violet changes for the second time to blue, the process is
interrupted, and the plate is rinsed and dried over an alcohol flame.
This silver plate now renders all colors of the spectrum; the blue and
violet strongest, the yellow weakest. Heating to 100 degrees, during
which the film turns pink, increases its sensitivity, especially for yel-
low. 4 The sensitivity of the silver chloride layer to colored light de-
pends upon the thickness of the layer and the strength of the chlo-
rinating solution, also on the purity of the silver, which should not
contain even 10 percent copper. 5 Copper chloride imparts to the colors
greater liveliness than chlorine water alone. When weak chlorine is
used, the yellow in particular is reproduced, while concentrated chlo-
rine water renders especially the red and the orange. A mixture of
magnesium chloride and copper sulphate seemed advisable. 0 Later
Niepce de Saint-Victor chlorinated with chloride of lime; this alkaline
bath gives less sensitive layers, but is very simple. The most pleasing

666

PHOTOCHROMY

photochromes made on chlorinated silver plates are the work of Niepce
de Saint- Victor, who exhibited them at the Paris Expositions of 1862
and 1867. 7

One of these Niepce heliochromes (a colored example) of 1867
came into the possession of this author from Ludwig Schrank; after
sixty years it still presents unchanged a remarkable liveliness of color.
It is protected by a mixture of lead chloride and dextrin. These original
photographs in natural colors on metallic silver plates are now ex-
tremelyrare, which is the reason the author ordered one of them repro-
duced in facsimile by chromolithography, as a remarkable document of
the history of photography, for the third German edition of this His-
tory. Insert III in that edition shows a halftone reproduction of this
original heliochrome by Niepce de Saint-Victor.

This at the same time establishes the fact that direct heliochromes
on silver subchloride do not fade by themselves, although they turn
gray rapidly in light; they cannot be fixed.

Poitevin experimented especially with the production of photo-
chromes with silver subchloride on paper. He turned back to the
earliest form of Seebeck’s experiments 8 and observed that by suitable
admixtures, especially oxygen containing salts, the violet silver chloride
on paper gives better color images.

He produced on ordinary unprepared photographic paper first a
silver chloride layer, by floating it on a solution of common salt, then
on a silver nitrate solution. After washing out the free silver nitrate,
the paper was placed in a very weak stannous chloride solution; the
tray was then exposed to diffused daylight for from five to six minutes,
when the paper was taken out and thoroughly washed. In order to in-
crease the sensitivity of the violet silver subchloride which had formed
on the paper, it was treated with a mixture of potassium bichromate
and copper sulphate. The paper, dried in the dark, developed under
colored paintings on glass or by a projection apparatus, gave colored
impressions which could be fixed to some degree with sulphuric acid. 9
Later Saint-Florent 10 especially occupied himself with similar ex-
periments. Raphael Kopp 11 (died 1891) followed Poitevin’s method
and improved the reproduction of the colors by adding mercury nitrate
to the preparation of the paper, 12 employing the bath method.

Silver chloride emulsion papers are also suitable for the reproduction
of colors. The first obscure statements on this subject come down to
us from the year 1857. Colored images were sometimes obtained on

PHOTOCHROMY

667

collodion silver chloride; after fixation with potassium cyanide the
colors are supposed to appear 13 when subjected to the action of iodine
chloride vapors. More precise is the statement of Wharton Simpson,
who observed that collodion silver chloride paper (which we now call
“celloidin” paper), which under light had turned a slate gray, turns
under different varieties of colored glass to various colors. Under ruby
glass it turns red, and under an aniline green filter, green, and so forth. 14
This statement was found much later to be true for all modern collodion
and gelatine silver chloride printing-out papers (collodion and gelatine
printing-out papers) . 15

Dr. Wilhelm Zenker, 10 of Berlin (1829-99), collected in his Lehr-
buch der Fhoto chromic (Berlin, 1868) all the material published on
the subject up to that time, and he was the first to advance the theory,
which later became so important, that stationary light sources produce
the colors of thin laminae (layers); Rayleigh (1887) also explained
the origin of Becquerel’s color photography by stationary waves.

It was not until 1889 that Professor Otto Wiener (1862-1927) suc-
ceeded in experimentally and definitely demonstrating stationary light
waves. He gave, also, by his discerning study, “Farbenphotographie
durch Korperfarben und mechanische Farbenpassung in der Natur”
(1895) 17 an incontestable explanation of the creation of colors when
silver subchloride papers are exposed to light. He demonstrated that
Zenker’s explanation of the theory of stationary light sources does not
hold good for all these processes. In Becquerel’s method (with silver
plates and a homogenous layer of silver chloride, containing sub-
chloride) stationary waves act in combination with so-called pigments,
while in Seebeck’s and Poitevin’s paper images the colors of the image
are exclusively pigmentary.

The “pigments” originate in light, according to Wiener, in the fol-
lowing manner: a light-sensitive substance can be changed only by the
color rays which it absorbs. Light-sensitive red matter, therefore, is
not changed by red rays, because it repels them, and likewise light-sen-
sitive yellow and blue matter remains unchanged in yellow and blue
light, respectively. When, therefore, a light-sensitive substance is
capable by the action of light of assuming different colorings, it will
under the influence of red, yellow, and green rays change so long,
until it has turned red, yellow, and green, and the color remains during
further exposure. This property is inherent in Poitevin’s silver sub-
chloride, and this explains the origin of the colors; but none of these

668 PHOTOCHROMY

silver subchloride photochromes can be fixed, because the fixative
destroys the colors.

In consequence of these premises the investigations in photochromy
had to be pursued along two different directions: ist, photochromy
according to the interference method, which leads to Lippmann’s
method and, 2d, photochromy by the bleaching-out process.

LIPPMANN SOLVES THE PROBLEM OF FIXABLE DIRECT PHOTOCHROME
EXPOSURES BY THE INTERFERENCE METHOD ( I 89 I )

The greatest recognition for having produced and fixed photo-
chromes by direct exposure from nature is due to the physicist Gabriel
Lippmann, of Paris (1845-1921). Lippmann studied in Heidelberg,
received his doctorate in philosophy in 1873, went to Paris in 1875,
where he continued to study until 1878, when he became professor
of physics at the Sorbonne. His work dealt especially with the field
of electricity, to which he gave his “capillary electrometer,” a most
valuable instrument. He also contributed important studies on thermo-
dynamics and optical phenomena. Lippmann presented to the Paris
Academy of Sciences on February 2, 1 89 1 , his report on photochromy,
in which he described his famous method of photography in colors,
the so-called “interference” method, based on the action of stationary
waves ( Compt . rend,., 1891, CXII, 274). His first experiments were
carried on with silver bromide albumen plates sensitized for color with
cyanine. His successful experiments in the reproduction of the solar
spectrum in its colors aroused much attention in the scientific world,
because he had solved the problem of direct photography in natural
colors on silver haloid layers and the fixation of the color images.

In Lippmann’s method 13 a glass plate was coated with a “grainless”
(as fine grained as possible) color-sensitive film of albumen containing
potassium bromide, dried, sensitized in the silver bath, washed, flowed
with cyanine solution, dried, and then brought into optical contact
with a reflecting surface; the back of the plate is then flowed in a plate
holder of special form with pure mercury and exposed in the camera
through the glass side of the plate, so that the light rays which strike
the transparent light-sensitive film, are reflected in themselves and
create interference phenomena of stationary waves.

Then followed the development of the latent image, during which
the formation of silver as white as possible was striven for. After fixa-
tion with potassium cyanide solution and the drying of the image, a

PHOTOCHROMY

669

brilliant picture in colors appeared when viewed in reflected light.

Lippmann produced by his process such photochromes of the solar
spectrum and of the spectrum of an electric arc light. These color
images of the spectrum were only a few centimeters long and showed
good reproduction of color from blue to red.

As a light-sensitive material Lippmann used the albumen process,
along the lines of the old Niepce de Saint-Victor method, but employed
in place of silver iodide, silver bromide, and he sensitized with cyanine.

Such a color image of the spectrum Lippmann sent to this author,
who loaned it to the Technical Museum for Industry and Trade,
Vienna. The detailed description of the procedure is taken from a
letter from Lippmann to this author, dated June, 1892.

This letter discloses that Lippmann employed that particular process
which, among the processes known at the time, produced the finest
grain, namely, the albumen-bath process, omitting silver iodide from
his preparation and substituting pure silver bromide, thus ensuring a
more favorable color sensitizing. Owing to the extremely low light-
sensitivity of this method Lippmann confined himself to the photog-
raphy of the most luminous spectra. In 1892 Lippmann started on a
series of important experiments; he produced photochromes of natural
objects, such as paintings on glass, flowers, parrots, a landscape with
green trees and blue sky, on which work he reported on May 2, 1892
( Jabrbuch , 1893, p. 426).

Lippmann also made experiments for the production of photo-
chromes by his interference method without the use of silver salts.
He presented to the Paris Academy of Sciences on October 24, 1892,
color photographs in which albumen or gelatine with addition of
bichromates was used as the sensitive film . 19

In 1908 he conceived an idea which was as bold as it was original.
He proposed the production of photographic plates constructed in
imitation of an insect’s eye, on which plates a negative would be formed
without the use of a photographic lens, and the positive of which
would give a stereoscopic impression (Lippmann, in Compt. rend.,
1908; Jabrbuch, XXX, 1 170; also, Lippmann, in Journal de phys., 1908,
VII, 821; Bull. Soc. frang. phys., Proc. verbaux, 1911, p. 69). Lipp-
mann called this method “photographic integrale.”

Following this method, E. Estanave experimented with it and de-
scribed further details (Compt. rend., CLXXX, 1255; 1930, XXIV,
1405). Dr. Herbert E. Ives wrote on “Optical Properties of a Lipp-

670 PHOTOCHROMY

mann Lenticulated Sheet,” Journal of the Optical Society of America
( 1 9 3 1 » P- HO-

Lippmann was a member of the French Academy of Sciences and
was awarded the Nobel prize for 1908. He died in 1921 on board the
S/S La France, returning from Canada, where he had gone as a
member of a French mission. He died from an illness which he in-
curred owing to the hardships of the trip. An exhaustive biography
of Gabriel Lippmann is printed in the Bull. Soc. frang. phot. (1921,
pp. 299, 325).

INTRODUCTION OF “GRAINLESS” SILVER BROMIDE GELATINE FOR THE PRO-
DUCTION OF LIPPMANN PHOTOCHROMES BY THE BROTHERS LUMIERE

AND E. VALENTA (1892)

At first Lippmann worked with albumen plates, which were not very
sensitive. In 1892 the brothers Lumiere, in Lyons, produced their
first satisfactory Lippmann photochromes on fine-grained gelatine sil-
ver bromide plates. They reported their method March 23, 1892, to
the “Societe des Sciences Industrielles” at Lyons, 20 but this local publi-
cation was not transmitted to the technical journals and therefore
remained unknown in larger circles. Valenta, at Vienna, worked in-
dependently on the same method and published the process almost at
the same time. 21

The first publication by the Lumieres was written in general terms
and contained no detailed statement on the preparation of the gelatine
silver bromide emulsion suitable for Lippmann’s photochromes. This
description is first given by Valenta in September, 1892. The gelatine
silver bromide must be prepared and applied at a very low temperature
in order that the “ripening” and accompanying enlargement of the
silver bromide grain is avoided (Valenta, Die Photographie in natiir-
lichen Farben, 2d ed., 1912).

The light-sensitivity of these “grainless” gelatine silver bromide
films was essentially greater than that of the earlier albumen films,
but still very much less than those of ordinary gelatine silver bromide
plates. From this time on only gelatine emulsions were used for the
Lippmann process. The Lumiere brothers were the first to take the
portrait of a living person in natural colors, in the summer of 1893,
which they showed at the International Photographic Exhibition in
Geneva. It was a photograph of a girl, resting her head on her arm at
a table with a green background of grape vines and a glass of red wine

PHOTOCHROMY

671

on the table. This photochrome possesses particular interest as the first
photographic image of a human face in natural colors, taken directly
from nature.

The Paris Exposition of 1900 brought many such beautiful photo-
chromes from nature by Lippmann, Lumiere, and Neuhauss, of Berlin,
among them photographic portraits in everyday attitudes.

In 1893 Hermann Krone, at Dresden, demonstrated that Lippmann
photochromes can also be obtained without mercury mirrors by mere
reflection from glass.

Dr. R. Neuhauss, 22 at Berlin, who devoted himself very success-
fully to photochromy, was the first to demonstrate, in 1897, by the
aid of microphotographs of cross-sections, that at a two thousand times
magnification the lamellae of the silver precipitate become visible in
the interference image of the spectrum. In the same year he showed
that “grainless” emulsions, after developing and fixing, possess silver
grains of about 0.005 mm - in diameter.

For further development of interference color photography we are
indebted to Dr. Hans Lehmann (died September 19,1917,31 Dresden,) 23
who, in 1905 and the following years, occupied himself successfully
with these methods at the Zeiss works, Jena. Here he also constructed
improved apparatus with mercury holders for taking interference
photochromes, as described in his Beitriige zur T beorie und Praxis der
direkten Farbenpbotograpbie nach Lippmanns Methode (1906) and
in Photo graphiscbe Rundschau (1909) . Lehmann made, in 1906, micro-
photographs of the lamellae of photochromes, of monochromes as well
as of mixed colors at a 7000 times magnification, which he reproduced
by Spitzertype (see ch. xciii) .

Lehmann kept secret his good formula for the production of “grain-
less” and correct-color-sensitive gelatine silver bromide plates, made
for him by Richard Jahr, the dry-plate manufacturer at Dresden, and
only long after Lehmann’s death, in 1925, did Jahr reveal the prepara-
tion, for which the modern color sensitizers, pinacyanol, orthochrome,
and acridine orange were used. 24 With Lehmann the technique of
Lippmann’s photochromy reached its highest point.

In 1907 Lehmann made a color photograph of an oil painting (a
sample is reproduced as insert IV in the 1932 German edition of this
History ) . This was the first reproduction of a Lippmann photochrome
by the three-color halftone process. The plates were made by Schelter
and Giesecke, in Leipzig, and printed in Germany and England

PHOTOCHROMY

672

(Valenta’s Photographie in natiirlichen Far ben, 1909, Penrose’s Year-
book, 1907-8, and others). We are indebted to the Carl Zeiss Works,
of Jena, for the electrotypes.

Lehmann’s work ended abruptly in 1909, because in the meantime
A. and L. Lumiere had commercially introduced their autochrome
plates. They had solved the problem of photography in natural colors
in a more convenient and comparatively cheaper manner and ac-
complished the result with shorter times of exposure.

Although Lippmann’s interference photography has disappeared
from photographic practice, it still remains the culminating point of
the scientific solution of the problem of photography in natural colors
by direct exposure in the camera.

from lippmann’s “photographie integrale” to the kodacolor

PROCESS FOR COLOR MOTION PICTURE PROJECTION

The ingenious idea of Lippmann to provide the back of the photo-
graphic film with very many small lenses, analogous to the faceted
eyes of insects 25 was taken up by Albert Keller-Dorian, whose patents
go back to 1908. 28 The small lens-like raised parts (“wart lenses”) are
impressed on the back of the film with steel embossing cylinders. At
first the Keller-Dorian establishment made these with fifty-two cells
to the square centimeter, later the lens pattern was made much finer,
to about twenty-two on a square millimeter. The other side of the
film is coated with a panchromatic emulsion. A divided three-color
light filter (blue, green, red) is inserted. The small facets, or wart lenses,
of the embossed film project an image of the color light filters on the
panchromatic photographic film. From the film negative thus produced
diapositives are made with the use of acid permanganate or bichromate
baths (similar to the autochrome process) and they furnish motion
picture projections in color.

The firm Keller-Dorian belonged later to Berthon, in Mulhouse
(Alsace), who improved the method further for motion pictures in
color. He succeeded, in 1922, in producing a good experimental film
of short length, and in 1923 he produced in the south of France a
long color cinema film suitable for color projection. The method was
called in short the “K. D. B. process” (Keller, Dorian, Berthon).

Soon Berthon left the company, the reasons for this step not being
made public. Keller-Dorian died in 1924, and Brosse, another stock-
holder, also left, with two young engineers, and founded another

PHOTOCHROMY

673

company, the “Societe d’Etudes.” Berthon joined this company in
1926, while the Keller-Dorian company continued along the same
lines ( Filmtechnik , 1928, No. 7).

The rights for the Keller-Dorian-Berthon process were bought in
1928 by the Eastman Kodak Company, which, with its tremendous
resources, improved the process to a high degree. The Kodak Company
introduced special photographic and projection apparatus for the prac-
tice of the process, giving it the trade name “kodacolor,” and in the
same year put on the market films for amateur motion pictures in
color, 27 and widely advertised them. 28

The motion picture photographic lens (Cine-Kodak) has a light
intensity of f. 1.9. The colored light filter placed over the lens consists
of three filters next to each other (red, green, blue). The kodacolor
film bears twenty-two facet lenses on one square millimeter. The small
facet lenses, embossed on the film, act like photographic lenses and
photograph the object with a three-color filter through the film carrier
onto the light-sensitive film, which is strongly panchromatic. When
the exposed film is reversed, the light can penetrate the film only in
those parts where an exposure has taken place, and since an exact
repetition of the ray direction during exposure takes place in reversed
sequence, a picture in the natural color of the object is produced on
the screen.

PHOTOCHROMES THROUGH COLOR SELECTION BY THE
BLEACHING-OUT PROCESS

Color-printing methods, or photochromy, by the bleaching-out
process are based on the fact that light-sensitive substances are bleached
out only by those kinds of light which they absorb, while they are
not destroyed by light of their own color. Vogel (1813) and Grotthuss
had experimented with bleaching organic dyes in varicolored light
(see ch. xvii).

Herschel studied, in 1842, “the action of the rays of the solar spec-
trum on vegetable colors” 28 and determined on the basis of his obser-
vations that coloring matter is destroyed as a rule by those color rays
which possess the color complementary to the former. He cited the
example that orange-yellow dyestuffs are destroyed mostly by blue
rays; blue coloring matter by red, orange, and yellow light; purple
and carnation red dyes by yellow and green light.

But these observations were forgotten until Otto Wiener’s thorough

PHOTOCHROMY

674

investigations placed them again in the foreground and determined the
theory of the origin of pigmentary colors by the action of light.

Regarding the historical development of the bleaching-out process,
it seems that the publications of Raphael Ed. Liesegang in this field
are not yet fully appreciated. In the Photogr aphisches Arcbiv, pub-
lished by him, he recommended as early as 1889 (No. 633, p. 328) that
the primary colors, red, yellow, and blue, be mixed on paper and that
for this purpose fugitive coloring matter be employed. At the same
time he gives a perfectly correct explanation of the process by which
in such color mixtures the colors of the light source (for instance, from
paintings on glass) are reproduced.

In his Photographiscbe Almanach fi'tr 18 pi, Liesegang broadened
his statement by adding: “The (bleaching-out) process proceeds more
rapidly in oxygen.” A few years later Liesegang published 30 a series
of experiments which relate to the acceleration of the bleaching-out
of different aniline colors by the addition of various chemicals (stan-
nous chloride, oxalic acid, hydroxylamin, ammonium sulphocyanide,
lead acetate, tartaric acid, sodium carbonate, soap, etc.) , 31

Incited by Wiener’s investigations, E. Vallot, in 1895, produced for
the first time photochromes by the so-called “bleaching-out process.” 32
He mixed (led by the idea of applying three-color printing to the
bleaching-out method) fugitive red, yellow, and blue coal-tar dyes
(aniline purple, curcuma, and Victoria blue), and spread them on
paper, which now appeared black. This coating turned in sunlight
under colored transparencies blue in blue light, yellow in yellow light,
and red in red light, because red light, for instance, bleaches out the
blue and yellow coloring matter and permits, thus, only red to remain.
Unfortunately, this process of Vallot suffered greatly from lack of
sensitivity.

Ministerial Councillor Karl Worel, at Graz (Styria), as well as Dr.
R. Neuhauss, at Berlin, endeavored to shorten the required time of
exposure by searching for oxidizing substances which would accelerate
the bleaching-out of the coloring matter (and thus act as sensitizers)
and could be removed after exposure.

Worel used essential oils, especially one of the components of ani-
seed oil (anethol) for admixture to red, yellow, and blue coal-tar colors,
and while he failed to obtain a high sensitivity, he was able to use this
method for photography. He exhibited a collection of photographs
in pigmentary colors (made both in the camera and by contact print-

PHOTOCHROMY

675

ing) at the Amateur Photographic Club of Graz, November 12, 1901,
and published his method March 13, 1902, in the Bulletin of the
Academy of Sciences at Vienna. 33

At about the same time Neuhauss published his process in the
Photogr apbische Rundschau { January, 1902) and stated that he mainly
used oxidizing substances, like hydrogen peroxide, persulphate, etc.,
as an addition to the color mixture and that he had in this way ac-
complished a very considerable increase in light-sensitivity, providing
that the colors were transferred with gelatine on glass and that this
film was exposed while still moist. 34 Lumiere and Jougla at Lyons used
for the same purpose hypochlorides, and so forth (1913).

J. Szepanik, at Vienna, in 1902, also used three different dyes, but
not in a mixture; he applied them, with a suitable binding substance
(gelatine, collodion, etc.), in layers on top of each other, to paper. 35
Other photographic printing methods for the production of pictures
in color, such as those with leuco bases (D. Gros, 1901; E. Konig,
1904), the katatype invented by W. Ostwald (1902), and others, are
described in Handbuch (1926, Vol. IV, Part 2, and Vol. IV, Part 4).
All these methods, however, are at this time ( 1 93 2 ) practically incom-
plete, and all we can record is their origin.

Dr. J. H. Smith and Dr. W. Merkens, at Zurich, elaborated Word’s
work and produced “utocolor paper” for the bleaching-out process,
which was prepared with a mixture of the primary colors and with
the addition of anethol as sensitizer; it was placed on the market in 1907.

In 1910 Dr. J. H. Smith improved his utocolor paper, employing
new sensitizers for photochemical bleaching-out by using thiosinamine
and other combinations. With this improvement he participated in its
exploitation by the “Societe Anonyme Utocolor” (La Garenne Co-
lombes, Paris), which in 1911 made extensive efforts to introduce the
bleaching-out process as a printing method into general practice. The
firm produced beautiful picture folders with proofs on paper (from
autochromes, etc.) and improved the manipulation of utocolor papers. 35
The factory continued to work for several years, but all bleaching-out
methods for color selection, on which so much hope had been placed,
could not fulfill the expected results. 30

Chapter XCVI. photographic technical

JOURNALS, SOCIETIES, AND EDUCATIONAL INSTI-
TUTIONS

For the survey, incomplete as it must necessarily be, owing to lack
of space, of the influence which the early photographic journals,
societies, and educational institutions have exerted on photography,
we append a few statements. 1

FRANCE

The first notices in France on the daguerreotype were published
in the Comptes rendus de rAcademie de sciences. Subsequently the
growing interest in photography in the middle of the last century
caused the creation of photographic societies and technical journals.
In 1851 was founded the “Societe Heliographique de Paris” (by de
Monfort), who had as his cofounders Niepce de Saint-Victor, Ed.
Becquerel, Chevalier, Le Gray, Regnault, and others. The journal of
the society was La Lumiere, of which twelve numbered volumes ap-
peared, 2 which are important for the history of that time.

The Societe fran^aise de Photographic was founded November 15,
1854, at Paris. The history of this society is published in a pamphlet
by Pector ( Notice historique, 1905), with portraits of its presidents
Regnault, Balard, Peligot, Janssen, Marey, Lippmann, Laussedat, Da-
vanne, and Sebert. An exhibition of artistic photographs is held regu-
larly as “Salon International d’Art Photographique de Paris” by the
Societe fran^aise de Photographic and the Photo Club.

This Paris photographic society soon outstripped all other earlier
photographic societies in France, and it achieved, through its Bulletin,
which has been printed since 1855 and is still being published, as well
as through its prize competitions, a great and lasting influence on the
progress of photography. It also awarded honor medals, such as the
“Peligot-Medaille,” founded by the chemist Peligot, which bears the
portraits of Niepce and Daguerre.

We must mention here the successful prize competitions and the
great encouragement given by this society. Most successful were those
of the Duke of Luynes, in 1856. The duke had seen the first photo-
graphic prints of Poitevin produced with printer’s ink, which were
exhibited in 1855, and in view of the, to be sure, still imperfect examples
desired to hasten the solution of the problem of the production of

JOURNALS, SOCIETIES, AND INSTITUTIONS 677

permanent photographic prints. He donated, in 1856, through this
society, two prizes, which led to the invention of pigment printing,
gum printing, photolithography, and collotype.

In the last century was established at Paris a technical school on a
large scale, the “Ecole Municipale Estienne,” 3 or “Ecole de Livre,”
which is the oldest of its kind. Typographic printing, lithography,
and the photomechanical processes were taught here. The photographic
department was directed by the excellent technician in reproduction
and technical writer L. P. Clerc. The school receives great encourage-
ment from the city authorities because of its services to the growing
generation in the printing industry.

At the old and extensive “Ecole des Arts et Metiers,” at Paris, L.
Vidal, who has been referred to many times in this History, taught
for many years as professor of photography.

Although in various places in France the subjects of photography,
photographic optics, and the technique of reproduction had been
taught for many years, a special school devoted to photography and
cinematography was not established until a commission of French tech-
nical experts had visited other national institutions for this purpose,
among them the Graphische Lehr- und Versuchsanstalt in Vienna,
and had made themselves acquainted with their organization. An edu-
cational institute for photography and cinematography was opened
in Paris on November 15, 1926, and was directed by L. P. Clerc and
Paul Montel. 4 Both theory and practice were taught there.

The first journal devoted to the application of photography in medi-
cal science was the Revue medico-photographique des hopitaux de
Paris, founded in 1 869 by Dr. de Montmeja. It was richly illustrated
with Woodbury types as early as 1875.

Of the many photographic societies in Paris we mention also the
“Photo-Club de Paris,” the “Societe frangaise d’Amateurs Photo-
graphiques,” and the “Stereo-Club de Paris.” An exhaustive list of
French photographic societies is contained in the Agenda Lumiere
(1930).

ENGLAND

Of the English scientific photographic technical societies, the Lon-
don Photographic Society, founded in 1853, achieved special impor-
tance in the development of photography. The Royal Photographic
Society of Great Britain grew from the meetings of a few photog-

6 7 8 JOURNALS, SOCIETIES, AND INSTITUTIONS

raphers, who used to come together during 1851 and 1852 in the rooms
of the Art Journal. The foundation of this photographic society took
place on January 20, 1853, at the clubhouse of the “Society of Arts.”
At that meeting some members offered a resolution to found, not a
new society, but only a branch of the Society of Arts; but the motion
failed to pass and thus this photographic society was founded, with
Sir Chas. Eastlake as its first president. The first photographic exhibi-
tion took place on January 3, 1854, which Queen Victoria and the
Prince Consort Albert attended with their retinue; from that time the
interest of the royal family in photography never waned. The society’s
journal, The Photographic Journal, appeared in March, 1853, but met
with financial difficulties and ran into debt which amounted to £335
i n 1 860. In 1 890 the number o f members had so increased and the finan-
cial condition was so satisfactory that the society was able to move into
its own quarters at 35 Russell Square, London. In 1 894 Queen Victoria
granted it the title “Royal Photographic Society of Great Britain.”

The society founded in 1878 its silver “Progress Medal,” awarded
annually. This medal was bestowed in the first years of its existence up-
on W. de W. Abney, 1878; W. Willis, 1881; L. Warnerke, 1882; W. B.
Woodbury, 1883; J. M. Eder, 1884; Abney, 1890; J. Waterhouse, 1891;
P. H. Emerson, 1895; Thomas R. Dallmeyer, 1896; G. Lippmann,
1897; Hurter and Driffield, 1898; Louis Ducos du Hauron, 1900; R. L.
Maddox, 1901; Joseph Wilson Swan, 1902; Frederic Eugene Ives, 1903;
Paul Rudolph, 1905; Janssen, 1906; E. Sanger-Sheppard, 1907; John
Sterry, 1908; A. Lumiere and his sons, 1909; etc.

Photography is taught in almost all the large cities of Great Britain;
for instance, at the Municipal College of Technology in Manchester,
where there is a department of photographic technology, where the
well-known phototechnicians R. B. Fishenden and Charles W. Gamble
taught (until 1932).

The Photomicrographic Society, founded at the turn of the 19th
century, devotes itself specially to its own field and has published, since
1915, its own journal.

A very exhaustive list of the numerous photographic societies in
Great Britain is published in the British Journal Photographic Almanac
(1931, p. 144).

The photographic societies of England, previously associated in local
or sectional groups, for the promotion of their interests formed in
1891 “The Affiliation of Photographic Societies” with the Royal

JOURNALS, SOCIETIES, AND INSTITUTIONS 679

Photographic Society of Great Britain, which was reorganized in 1930
as “The Photographic Alliance,” comprising (1932) about 300 societies
in Britain and overseas, with 22,000 members. The Photographic Red-
Book, first issued in 1900, is the official yearbook of the Alliance and
lists all the federated societies and their activities.

In Scotland a photographic society under the patronage of Prince
Albert was founded in 1856. Sir David Brewster was its first presi-
dent. 5 Many other small societies started in various places and func-
tioned for a longer or shorter time (see footnote 3, ch. xliv).

In Bombay, India, a photographic society also was founded in 1855,
which published the Journal of the Photographic Society of Bombay.

In 1854 the Liverpool Photographic Journal was founded, which
was merged in 1856 with the great London publication The British
Journal of Photography, which still exists. The British Journal Photo-
graphic Almanac was first published in September, 1859, as a supple-
ment to the British Journal. It has appeared annually since then. In the
Almanac of 1931 (p. 140) the succession of editors is enumerated. In
1856 The Photographic News was founded at London.

AMERICA

The first photographic technical journals in the world were pub-
lished in America. The first of these devoted especially to photography
appeared in Boston under the title The Daguerreotype; a magazine
of foreign literature and science, compiled chiefly from the periodical
publications of England, France and Germany, in 3 volumes from
1847 to 1849. [The Daguerreotype quoted was not a photographic
journal, but was devoted to general literature. There is also in the
Epstean Library, Columbia University, a three-volume journal en-
titled, 1 1 dagherotipo (Turin, 1840-42). In the preface of Volume I
the editor gives a reference to the daguerreotype and illustration of
a daguerreotyper’s outfit. The journal described immediately follow-
ing was really the first periodical devoted to photography in the world.
Translator’s note.J

S. D. Humphrey, at New York, founded The Daguerreian Journal;
Devoted to the Daguerreian and Photogenic Art . 6 It made its appear-
ance in November, 1 850, changed its title in 1 853 to Humphrey's Jour-
nal of the Daguerreotype and Photographic Arts and the Sciences and
Arts Pertaining to Heliography (8 volumes, V-XII, 1853-62); and
from thattimeitwas published as Humphrey's Journal of Photography

68o JOURNALS, SOCIETIES, AND INSTITUTIONS

and the Allied Arts and Sciences (1862-1870) edited by John Towler.

Humphrey's Journal was not without competition. H. H. Snelling
published, in 1851, The Photographic and Fine Art Journal, New
York, of which the first series ran until 1853, the second from 1854
until about i860. Snelling died in 1897, eighty years old, at St Louis,
Missouri.

In America not only was the practical side of photography taken
up but also it was promoted by scientific investigation, which is
evidenced by the Franklin Institute at Philadelphia, founded in 1824,
where Elliot Cresson, a wealthy promoter of science donated, in 1 848,
funds for a gold medal of honor, which has been awarded by the
institute in all fields of science, including photochemistry. The fund
and the award is managed by the institute.

INTERNATIONAL EXHIBITIONS AT LONDON AND PARIS

The progress of photography was presented to the general public
for the first time at the International Universal Exposition at London
(1851), and at Paris (1855). 7 These were followed by numerous
exhibitions of photography at London, Paris, Birmingham (September,
1857), Vienna, Berlin, etc., and brought forward many valuable im-
provements in the art.

GERMANY AND AUSTRIA

In German literature Dingler’s Polytechnisches Journal the most
important technical organ, collected reviews from French, English,
and German photographic publications from 1839, and as late as the
1880’s still printed comprehensive reports.

The first photographic journal in German was published in 1853 by
the photographer, painter, and technical government official, Wilhelm
Horn, at Prague. The first number appeared in December, 1853
Horn's Photographisches Journal; Magazin usw. fiir Photographen,
Maler, Zeichner und Freunde dieser Kunst. It appeared twice a month
(1854-65, Vols. I-XXIII), and printed articles only on daguerreotypy
and collodion. In the fifties it was of great importance, but it soon lost
its reputation and it ceased publication in 1865.

The first German textbook on photography, Repertorium der
Photographie (Vienna, 1846) was written by A. Martin, librarian of
the Polytechnical Institute, Vienna. Martin, from the discovery of
photography, was one of the first amateur photographers and promoted

JOURNALS, SOCIETIES, AND INSTITUTIONS 68 1

photography at the Polytechnikum, Vienna. During the years 1855-
57, urged by Martin, Karl Josef Kreutzer, 8 of the library of the Poly-
technikum, edited the J abresbericht uber die Fortschritte und Leis-
tungen im Gebiete der Photo graphie mit genauer N achweisung dei
Liter atur, Vienna, and he founded, in i860, the Zeitschrift fur Photo-
graphie und Stereoskopie.

Both Kreutzer’s Jahresbericht and his Zeitschrift contain exhaus-
tive references to contemporary technical literature and are rich
sources for the historian.

The photographer M. Weingartshofer published, in 1 857, at Vienna,
the periodical Photograpbisches Album, which was distinguished as
the foremost illustrated technical journal by its excellent photographic
inserts and other illustrations. The periodicals mentioned above were
followed by the important publication Photograpbisches Archiv,
founded in i860 and edited until 1896 by Paul E. Liesegang, and by
R. E. Liesegang until 1897; also by H. W. Vogel’s, Photographische
Mitteilungen; and then by Photographische Korrespondenz and nu-
merous other technical journals.

The Photographic Society of Vienna is the oldest organization of
its kind in German countries. It was founded in 1861 by the Friends
of Daguerreotypy, who met in 1840 at the home of Karl Schuh, in
Vienna. The founders were representatives of professional photog-
raphy and men of science and art. 8 Regular meetings provided contact
between the members of the circle, who kept themselves informed
in this manner about the progress of photography at home and abroad.
Small exhibitions and a Wander album (circulating portfolio), which
was also sent to the provinces, propagated interest in photography in
wider circles. The first president of the society was the librarian A.
Martin (1861-66), and the Academy of Sciences placed a hall in its
building at the disposal of the society for its monthly meetings, which
courtesy it enjoyed until May, 1931. Martin’s successor as president
was Dr. Emil Hornig (1828-90), the son of Professor Dr. Josef Hornig
of the University of Vienna. He studied chemistry at the technical
college, and in the fifties became professor of chemistry at the govern-
ment technical high school, Vienna. Here he had a small chemical
laboratory at his disposal for photographic experiments. He furnished
the inspiration for the promotion of scientific endeavor in the photo-
graphic society, initiated prize essays on work in this field, and edited
his journal, the Photographische Korrespondenz, along these lines.

682 JOURNALS, SOCIETIES, AND INSTITUTIONS

After the death of Dr. Hornig, in 1890, Ottomar Volkmer, director
of the Government Printing Office, became president of the Vienna
Photographic Society, a position which he occupied until his death,
in 1901. He was succeeded by the author of this History. During the
latter's incumbency (1906) the society was granted the title “Imperial
and Royal Photographic Society,” with the privilege of using the im-
perial eagle as coat of arms in recognition of its public service, a right
which, after the Republic came into existence, was confirmed as far
as the use of the coat of arms was concerned. The society was also
honored by the city of Vienna, under the mayor Dr. Neumeyer, by
the bestowal of the Gold Salvator Medal. The Photographic Society
of Vienna awards several medals of honor for outstanding achieve-
ments. The earliest award was established by Baron Friedrich von
Voigtlander, who donated on May 7, 1868, a capital of 4,500 florins
for members of the society.

President Homig founded, in 1 876, the Medaille der Wiener photo-
graphischen Gesellschaft, which may be awarded also to nonmembers
for distinguished efforts in the field of photography.

The Josef Lowy Foundation, amounting to 10,000 kronen, was
given by Mrs. Mathilde Lowy (died 1905) in 1904 as a prize for out-
standing work in the field of photography.

The official publication of the society was at first Kreutzer’s Zeif-
schrift fur Pbotographie; after 1864 Ludwig Schrank’s Photograpb-
ische Korrespondenz, which is the only German photographic tech-
nical journal which has been published regularly.

The Photographische Korrespondenz was edited from 1864 to 1870
and from 188410 1905 by Ludwig Schrank (1828-1905). He was not
a professional photographer, although temporarily he had charge of
a studio in Vienna. He was an accountant in the Ministry of Agricul-
ture, the department for direction of sales for mine production. At
that time Austria still had a lively mining output, which the govern-
ment had developed— for instance, the mercury mines in Istria, the
silver and uranium mines in Joachimstal (Bohemia), the salt mines in
Galicia, etc.

Schrank was an ingenious, many-sided man, a composer and a witty
journalist. He kept in close touch with all the members of the society.
In the sixties he engaged for a short time in photolithography (Phot.
Korr., June, 1905). This is where he realized the desire of the profes-
sional photographers for a practical technical journal, satisfying the

JOURNALS, SOCIETIES, AND INSTITUTIONS 683
daily requirements of the craft. Kreutzer’s journal had become out of
touch with the practical needs of the time, and the necessity for a new
photographic journal became obvious. Ludwig Schrank brought the
Photogj aphis che Korrespondenz, and the first number appeared in
July, 1 864, to a high level of efficiency, and he was successful in finding
competent contributors. This journal contains a great deal of informa-
tion for historical studies. In 1870 Professor Homig bought the peri-
odical from Schrank, and he managed it from 1871 to 1884. Homig
applied himself especially to the scientific and technical side of pho-
tography and showed great interest in silver bromide emulsions, which
then had just made their appearance in the development of the photo-
mechanical processes. In 1882 the Frankfurt Verein zur Pflege der
Photographic (founded 1 874) selected the Photograpbische Korres-
pondenz as its official organ. In 1884 Professor Hornig, whose health
was failing, presented the journal as a gift to the Vienna Photographic
Society. The society again entrusted Ludwig Schrank with its manage-
ment, which he continued until his death, in 1905. 10 The Photograph-
ische Korrespondenz became of greater importance when, after 1889,
it became the official publication for the reports of the Graphische
Lehr- und Versuchsanstalt, Vienna.

The Vienna Photographic Society arranged an international photo-
graphic exhibition May 17, 1864, at Vienna, the first of its kind in
German countries, 11 and this was as fruitful in its way for the further
development of photography as the exhibitions of the photographic
societies of England and France had been.

Two years after the foundation of the Vienna Photographic Society
followed that of the Photographic Society of Berlin, brought about
on November 18, 1863, by Professor H. W. Vogel, who was its first
chairman. After some time, many members, including Vogel, who had
become dissatisfied, resigned and organized the Society for the Foster-
ing of Photography, which also elected Vogel as president, while Dr.
Franz Stolze took over the direction of the older society. In the course
of time the Photographic Society of Berlin became a trade association,
which is still in existence and which awards a Daguerre-Medaille in
recognition of services rendered in the field of photography. The
Society for the Fostering of Photography created in 1908 the Associa-
tion of German Amateur Photographic Societies and changed after the
World War to the German Society of Friends of Photography, which
since 1924, jointly with several large amateur photographic societies,

684 JOURNALS, SOCIETIES, AND INSTITUTIONS

has formed the German Photographic Society (Deutsche Photograph-
ische Gesellschaft) .

The official organ of the Society for the Fostering of Photography
was the Photographiscbe Mitteilungen; the first number, edited by
H. W. Vogel, appeared in April, 1 863. This journal became important,
for in it was published the work of the department of photochemistry,
which Vogel directed. 12 This society organized the first International
Photographic Exhibition at Berlin in 1865, which brought as good
results as the one in Vienna in 1864.

The Berliner deutsche Photographen Verein had at first chosen the
journal Das Licht as its public organ, which had no great influence.
In 1865 Dr. Stolze founded the Photo graphisches Wochenblatt, which
was very valuable, but ceased publication years ago.

The interests of the technical workers engaged in the field of re-
production were carried on by the Verband der Chemigraphischen
Anstalten Deutschlands und der Tiefdruckereibesitzer.

The trade paper for those engaged in manufacture and sale of photo-
graphic equipment, Die photographiscbe Industrie, Berlin, managing
editor Karl Weiss, was founded in 1902 and became an important
vehicle for phototechniques.

To the above-mentioned publications must be added the German
periodicals for scientific photography, for photogrammetry, for motion
picture and film technique, and others representing special fields.

AMATEUR SOCIETIES

The development of artistic photography was in a great measure
due to the amateur photographic societies formed during the last dec-
ade of the nineteenth century, especially to those at London, Vienna,
and Paris. The exhibitions of these societies, as well as the impetus which
they gave to pictorial photography by their enthusiasm and official
publications, acted as a guide and inspiration for the progress of photog-
raphy, the youngest of the arts. Several of these amateur clubs issued
periodicals, such as the Paris Photo-Club, which has published its
Bulletin since 1890, the Vienna Camera Club, and many others.

The first of these amateur societies in a German country was the
Club of Vienna Amateur Photographers, later called the Vienna
Camera Club. It was founded March 31, 1887, and soon gained great
importance (Phot. Korr., 1887, p. 226). It was one of the first of its
kind on the Continent. From September to October, 1888, it arranged

JOURNALS, SOCIETIES, AND INSTITUTIONS 685

an international exhibition, which presented the progress of amateur
photography and its importance in art, science, and industry. The
Vienna Camera Club published the Wiener Photograpbische Blatter
(1894-98), which devoted itself especially to the artistic side of pho-
tography and was notable for its beautiful illustrations. This organ
was supported by substantial contributions from wealthy amateurs,
but it ceased publication after a few years.

Other amateur societies at Vienna were the Photo Club (since 1899,
founded in 1897 as the Amateur Photo Club), and the Vienna Club
for Amateur Photographers, founded in 1903, under whose president,
Dr. Emil Mayer (1907-27), a prominent amateur and attorney-at-
law, the bromoil and bromoil transfer printing processes were popu-
larized by publications, lectures, and exhibitions. The Society for
Photographic Art and the Wiener Lichtbildner-Klub, founded in 1 9 1 1 ,
must also be mentioned.

These and other similar Austrian societies united in the Federation
of Austrian Amateur Photographers, just as happened in other coun-
tries.

PHOTOGRAPHIC EDUCATIONAL INSTITUTIONS

The earliest private photographic school in Germany was probably
that established by Dr. Julius Schnauss (1827-95) at Jena. On May 1,
1 855 , he opened his school with twelve pupils; he directed it for fifteen
years and taught the current practical methods, especially the wet
collodion process, which was not generally known at that time, for a
fee of 20 to 25 thaler ($15 to $18.50). The biography of this dis-
tinguished teacher of photography may be found in Phot. Korr. (1895,
p. 365). 13

Another private school was established by W. Cronenberg, in 1858,
at Schloss Gronenbach, Bavaria. This was a boarding school where
instruction was given in the different branches of photography and
later in the technique of reproduction. This school was very successful,
and it did not close until 1900. Cronenberg then moved to Munich,
where he started a reproduction establishment; he died there soon
afterward. He wrote numerous articles for the Jahrbucb and an excel-
lent handbook entitled, Praxis der amerikanischen Photogravure
(1899), which was translated into French by G. Fery.

Owing to the lack of schools for teaching photography in most of
the industrial centers, the larger firms dealing in supplies for photog-

686 JOURNALS, SOCIETIES, AND INSTITUTIONS

raphers did not stop at merely presenting their wares for sale, but
also instructed buyers in using and manipulating them. We have already
referred in Chapter XLIII to such a studio, conducted by the firm of
Wilhelm Eduard Liesegang, at Elberfeld (Germany), in 1857.

Seventy years ago the teaching of photography was confined to the
wet and dry collodion processes, to some photographic printing and
light-tracing methods, and to elementary photochemistry. In order to
present a view, we add to the above-mentioned (Schnauss, Krone,
Cronenberg), a survey of educational facilities in 1863.

Vienna: University, W. Burger.

Berlin: H. W. Vogel commences photographic courses at the
trade school.

Leipzig: University, Dr. Weiske.

Stuttgart: Royal Wiirttemberg Center, Dr. Haase.

Marseille: Public lectures, Leon Vidal.

Gent (Belgium): Public lectures, Prof, de Vylder.

London: Kings College, Hardwich, Sutton and Dawson.

Paris: Ecole Imperiale des Ponts et Chaussees and Ecole Imperiale
du Genie Maritime.

The importance of photography for professional use, as well as for
the graphic arts, trades, and science, was also recognized by the intro-
duction of a lecture course at the higher governmental educational
institutions.

In Germany a professorship was first established in 1864 at the
Trade Academy in Berlin, to which Dr. Vogel was called as instructor;
he was made full professor in 1873. After the establishment of the
Technical College at Berlin-Charlottenburg in 1879, Professor Vogel
received the professorship for photochemistry and scientific photog-
raphy and was provided with suitable laboratories and photographic
studios. There he successfully promoted photography and instructed
a large number of students. Vogel was succeeded, after his death
(1898), by Professor Dr. A. Miethe. After Miethe, who died in 1927,
Professors Dr. Erich Stenger, Dr. Erich Lehmann, and O. Mente con-
tinued the instruction.

Another deserving earlier protagonist in photographic education
in Germany must be mentioned here. In 1853 Hermann Krone (1827-
1916), who had worked at photography, suggested to the Saxon
government the establishment of a professorship for scientific photog-
raphy, but the petition was denied “owing to lack of funds.” Per-

JOURNALS, SOCIETIES, AND INSTITUTIONS 687

sisting in his efforts, Krone succeeded in being called to the Polytech-
nikum at Dresden as instructor of photography 1870-71. There he
worked for the first nine years without any financial support from
the government. For the next twelve years he received 300 marks
($75) annually. In 1898 Krone was appointed assistant professor of
photography at the Technical College, Dresden, and later full professor.
He retired in 1907, 80 years old, with distinguished honors. After
Krone’s retirement the Saxon government had to provide the necessary
funds, largely exceeding the inadequate remuneration so modestly
accepted by Krone. It is said that Heinrich Ernemann, the head of a
great industrial concern, intervened with the government and induced
the Ministry to provide the sum required to establish a full professor-
ship, to which Professor Dr. Robert Luther (born in Moscow, 1868),
photochemist, pupil of Ostwald and former assistant professor for
physical chemistry at Leipzig, was appointed in 1904. The new building
of the Scientific Photographic Institute at the Technical College at
Dresden was opened in October, 1913.

At the University of Berlin Professor John Eggert lectured (1930)
on the “Basis and Uses of Photography,” the practical work being
done in the former “Agfa” photochemical laboratory.

Today Professor Dr. Fritz Weigert lectures at the University of
Leipzig; at the University of Giessen, Professor Dr. K. Schaum; at the
Technical College in Darmstadt, Professor Dr. Fritz Limmer; at the
Technical College in Karlsruhe, Professor Fritz Schmidt on photog-
raphy (since 1888) and Professor Dr. J. Kogel (since 1921) on photo-
chemistry. Raphael Ed. Liesegang presents photochemistry at the
Institute for the Physical Basis of Medicine at Frankfurt a. M.

PHOTOGRAPHIC EDUCATION IN VIENNA; FOUNDATION OF THE
GRAPHISCHE LEHR- UND VERSUCHSANSTALT

As early as 1858 Dr. J. J. Pohl, professor of chemical technology,
lectured from time to time on photography and microphotography
at the Vienna Polytechnikum. At the University of Vienna the pho-
tographer Wilhelm Burger taught photographic practice for a few
terms in the 1860’s to the students of the Institute for Physics, which
had been located in a private house since 1 85 1 , 14

Professor Dr. Josef Stefan (1835-90), the famous physicist, was
the director of the institute. Wilhelm Burger gave his photographic
course, with Stefan’s permission, at the institute. The classes were

688 JOURNALS, SOCIETIES, AND INSTITUTIONS

held in a few small rooms, next to a water tower tank into which the
water used at the institute was pumped; a large garden was also at
his disposal. The subjects taught were chiefly the wet and dry collodion
processes. While there was no studio with a skylight, there was a great
opportunity for photography in the open air. Here Burger carried on
the preparations for his subsequent photographic expeditions, which
are reported on in Chapter XL VII. After Burger’s departure from
Vienna these photographic lecture courses were interrupted, about
1865; they were not resumed until thirty years later, by the lecturer
Hugo Hinterberger at the University of Vienna. 1 ' After Burger’s re-
turn he opened a photographic studio, was appointed court photog-
rapher and acted as secretary of the Vienna Photographic Society and
editor of the Photogr aphische Korrespondenz (obituary, Phot. Korr.,
1920, p. 135).

About the same time (1864) Dr. Emil Hornig lectured on photog-
raphy for one term at the Technical College, Vienna, but he did not
continue. He acted as president of the Vienna Photographic Society
and in later years did much for the development of photography. In
June, 1880, this author took up his residence at the Technical College
as private lecturer on photochemistry. He was at that time assistant
to Professor Pohl of the faculty of chemical technology, and he began
his lectures in the winter term of 1880-81.

At this time Dr. Hornig, as president of the Vienna Photographic
Society, directed the attention of the Ministry, in a petition, to the
necessity of fostering the new growth of photography by the establish-
ment of an experimental institution. The government also granted a
subsidy for the purchase of apparatus for this purpose. These, together
with the spectrographs purchased on the recommendation of this
author, were turned over to him as chief of the Government Chemical
Laboratory at the higher technical school.

ESTABLISHMENT OF THE FIRST INDEPENDENT GOVERNMENTAL EDUCA-
TIONAL INSTITUTION DEVOTED ESPECIALLY TO PHOTOGRAPHY AND THE

REPRODUCTION PROCESSES IN COMBINATION WITH A SCIENTIFIC PHOTO-
CHEMICAL EXPERIMENTAL LABORATORY

Dr. Hornig’s petition met with favorable consideration by the Aus-
trian government.

This author explained the extensive plans for the establishment of
an institute for photographic education and research at a lecture held

JOURNALS, SOCIETIES, AND INSTITUTIONS 689

on January 29, 1885. The scheme of operation evolved by him recom-
mended to the Ministry of Education a comprehensive combination of
an educational institution for photography together with scientific
laboratories and a department for the cultivation of the graphic arts.
The Minister of Education, Baron Paul Gautsch von Frankenthurm,
and Count Vincent Baillet-Latour took great interest in the matter
and called a conference at which it was decided to accept the report
of this author for a three-year course in photography and reproduction
technique, in combination with a scientific technical experimental
station, a photographic library, and a museum for graphic collections.
It was now necessary to find a suitable building. The city government
offered one of its school buildings, erected in 1859 and rebuilt in 1880,
which was enlarged and equipped with photographic studios by the
city building department. The Imperial and Royal Institute for Teach-
ing and Experimentation in Photography and the Reproduction Pro-
cesses was established on August 27, 1887, as a governmental institu-
tion directly responsible to the Ministry of Education and was com-
manded to open its work in March, 1888, under the direction of this
author. He called outstanding men as teachers to the institute (Jahr-
buch, 1889, p. 322; 1890, pp. 260 ff.).

The history of the origin and growth of the Graphische Lehr- und
Versuchsanstalt, Vienna, was described on the occasion of the fortieth
anniversary of the institution by the president of the Technical Ex-
perimental Station, Dr. Wilhelm Fr. Exner (1840-1931) from his own
recollections. 18

It is interesting to note how this institute has grown from small begin-
nings and how it has become world famous. I was privileged to observe
its growth. What were the educational conditions prevailing in this field
in the eighties of the last century, when photography, a new art, began
its victorious course in all fields of human endeavor? The Technical Col-
lege at Berlin had at that time a long-established course in photochemistry,
given by the famous Professor H. W. Vogel. The student was therefore
well provided for, but for the technician and the working man there was
no trade school either at Berlin or elsewhere. At the Salzburg Govern-
ment Trade School, about 1880, a photographic studio for teaching pho-
tography for reproduction was built in the attic, and there demonstra-
tions were given. Neither experimental research nor artistic photography
was represented. Another drawback was the lack of a local phototech-
nical industry. This photographic school could not last in such a primitive
form, and in 1887 it was discontinued. At Vienna the assistant for chem-

690 journals, societies, and institutions

ical technology, Dr. J. M. Eder, had established residence as lecturer in
photochemistry in 1880 at the Technical College. Dr. Eder had come in
contact with photography through his study of the photochemical prop-
erties of chromates. His investigations were awarded a prize by the
Vienna Photographic Society. Further scientific studies on silver bromide
emulsions and color sensitizers were made possible for him by a govern-
ment subsidy for the purchase of spectrum apparatus, granted, to him on
the petition of the Vienna Photographic Society. Thus modem photo-
graphic spectrum analysis was created in Austria by him, which subse-
quently became of such great importance for applied photography and
the production of motion films, as well as for the exact sciences.

Thus a foundation was laid for the later experimental institution. Then
Dr. Eder conceived the idea of gathering together under one roof scien-
tific photochemistry, applied photography, and its artistic development,
in a center for all Austria. The plan met with an enthusiastic reception.
As director of the Technological Museum for Industry, I recommended,
jointly with Hornig, that a section of this institute and one in his be set
aside for Dr. Eder’s projected institute, of which he was to be the direc-
tor. The Minister of Education, however, after hearing the report of his
referee Dr. Sonntag, stated: “Since the organization and the director are
ready at hand, the government will proceed with the undertaking if the
city authorities will provide a suitable building for its use,” which is
what happened. The Minister then entrusted Professor Eder with the
drawing up of the final plan of organization and with the starting of the
activities of the Lehr- und Versuchsanstalt fiir Photographie und Repro-
duktionsverfahren. The institute, which in March, 1888, was conducted
by Dr. Eder alone, was further extended after a few years by the ap-
pointment of the chemist Professor Valenta. Later the school was en-
larged by the addition of a section for typographic printing as well as by
the inclusion of photogravure, copperplate printing, copper and wood
engraving, and the installation of modem power presses. Dr. Eder direct-
ed the institute from 1888-1923 and gave it a world-wide reputation.
Both at home and abroad there is a keen appreciation of the accomplish-
ments of the institute in scientific investigation, in education, in technical
literature, and in the presentation of its work at international exhibitions.
The institute was so well organized by its founder and so firmly anchored
in the scientific, industrial, and artistic world, that it has weathered all the
storms of war and postwar times and is now able to celebrate its fortieth
anniversary in the well-earned joy of its labors. Director Eder was suc-
ceeded by Professor E. Valenta, who for years had supervised the experi-
mental section, but who soon retired.

May these lines awake the recollection of the work of those meritori-

JOURNALS, SOCIETIES, AND INSTITUTIONS 691

ous pioneers of old Austria, who created an institution of which we may
well be proud, which has served as an example for all later establishments
of its kind and has surpassed even the older Paris school, Ecole du Livre
(Estienne).

In 1892 a separate course for photochemistry was initiated at the
Technical College of Vienna, to which this author was appointed pro-
fessor, retaining his position as director of the Graphische Lehr- und
Versuchsanstalt, where the university lectures and practical photo-
graphic work were held once a week. The personal union created thus
between the two institutions brought about a close scientific relation-
ship, which contributed greatly to the well being of the institute.

On the petition of the Association of Printers at Vienna, the es-
tablishment of a section for printing and illustration was decided upon,
and the enlarged institute was designated as “Graphische Lehr- und
Versuchsanstalt” (1897), comprising now four sections: the first, the
educational section for photography and reproduction processes; the
second, the educational branch for the book and illustrating trades;
the third, the laboratories; and the fourth, the graphic and apparatus
museum and the technical library.

The institute trained many capable students. Their numerous ac-
complishments in the field of photomechanical investigation are incor-
porated in many contributions to the literature of the craft. The results
in the field of applied photography and the photomechanical repro-
duction processes have been made public by many proofs, and the
artistic side was carefully fostered. This gained for the Graphische
Lehr- und Versuchsanstalt prizes at many exhibitions, for example,
at Paris, 1900, at St. Louis, 1904, at Dresden, 1909, at Leipzig, 1914, not
only as an educational institution but also in competition in the field
of graphic practice and in scientific technical investigation. 17

In 1913 the Graphische Lehr- und Versuchsanstalt celebrated its
twenty-fifth anniversary and published a richly illustrated history of
the institute, consisting of 1 2 7 pages and 56 inserts. All the work con-
tained in this volume, both printing and illustrations, was executed
at the institute. The artistic inserts represent distinctive achievements
in the fields of scientific, technical, and artistic photography and re-
production processes and are an excellent testimony to the teaching
staff.

For the study of the history of photography our interest lies es-
pecially in the historic collections relating to photography and the

6 9 2 JOURNALS, SOCIETIES, AND INSTITUTIONS

photomechanical processes, the collection of lenses and apparatus, and
an extensive technical library started by this author and managed with
expert knowledge by his colleague the custodian of the collections,
Eduard Kuchinka. Here we wish to pay a special tribute to Eduard
Kuchinka, a valued contributor to this history of photography; un-
fortunately he died suddenly before this new edition was published.
£The translator, who knew Mr. Kuchinka personally, joins in this
tribute of respect for his specialized intelligence and all-embracing
knowledge in his field of endeavor.]

Eduard Kuchinka (1878-1930), born in Bohemia, was a grandson
of the well-known portrait photographer Carl Kroh, of Vienna. He
went to school in Vienna and learned photography in his grandfather’s
studio. He attended and finished the course for photography at the
Graphische Lehr- und Versuchsanstalt and then went into the photo-
graphic business.

In 1 898 this author appointed him an official in the administrative
department of the institute, and later he became custodian of collec-
tions and library. His knowledge of the history of photography was
very extensive and thorough, and he was one of the few who knew
the early, now unused and practically forgotten, photographic pro-
cesses and apparatus.

He wrote the monograph Die Photoplastik (1926) and, jointly with
this author, Daguerreotypie, Talbot y pie und Niepgotypie (1927);
also numerous historical articles for the Jabrbuch, Photographiscbe
Korrespondenz, etc.

Kuchinka served in the World War, first on the Eastern front and
later on the Italian border. He returned to Vienna and in 1930 died
suddenly from heart failure (obituary in Jabrbuch, Vol. XXXI). His
successor as librarian is Adolf Schwirtlich.

Professor Valenta was succeeded as director of the institute by Pro-
fessor Dr. Rudolf Junk, with Professor Otto Krumpel at the head of
the laboratories and Dr. Jos. Daimer as professor of chemistry (Jabr-
buch, 1921-27, XXX, 2).

LATER GERMAN PHOTOGRAPHIC SCHOOLS

The Lehr- und Versuchsanstalt fur Photographic, Lichtdruck und
Gravure, at Munich, was founded by the Photographic Society of
Southern Germany, with the support of the city and the state, and
opened in October, 1900.

JOURNALS, SOCIETIES, AND INSTITUTIONS 693

The first director, G. H. Emmerich, conducted a business in photo-
graphic equipment and consequently had a wide acquaintance in the
profession. He organized the school and directed it until 1919. He
was succeeded by Professor Hans Sporl, with Professor W. Urban
teaching photochemistry.

In 1906 the study of collotype and photogravure was added, and
the name of the school was changed to “Lehr- und Versuchs-Anstalt
fur Photographic, Lichtdruck und Gravure.” In 1909 the school re-
ceived without cost a former hospital building for its use, which was
opened in May, 1911.

The government did not take over the school until July 1, 1921,
when the name was changed to “Higher Professional School for Photo-
technique.” Soon afterward a branch was added for motion picture
technique (Professor Konrad Wolter).

In 1924 the section for photoengraving and collotype, which had
been in existence for a number of years, was discontinued as no longer
successful and because the photoengravers and lithographers of Munich
refused financial support for its continuation. The rooms vacated by
this section were then used by the motion picture department. Finally
the school was called “Bavarian Government Institute for Photo-
graphic Procedure (Lichtbildwesen) at Munich.”

In 1893 the very old Leipzig Art Trades Academy and Art Trades
School, founded in 1764, added a department for photomechanical
reproduction processes, directed by Dr. G. Aarland. In 1901 it received
the title “Royal Academy for the Graphic Arts and the Book Industry
of Leipzig”; it was devoted entirely to the graphic printing process.

The photographic school of the Lette Society for Fostering the
Education and Practical Training of Women, Berlin, was founded
in 1890 under the direction of Dr. Dankmar Schultz-Henke (died
1913), a former assistant of Dr. H. W. Vogel. It is now a govern-
ment technical high school under the direction of Marie Kundt and
one of the largest trade schools of its kind in Germany.

GOVERNMENT AND INDUSTRIAL UNDERTAKINGS AS PATRONS OF PHOTOG-
RAPHY; ARCHIVES FOR THE HISTORY OF PHOTOGRAPHY

The publications of the great governmental and private industrial
graphic institutions were of great importance for photography. This
was recognized especially by A. Auer von Welsbach, director of the
Government Printing Office at Vienna, in the fifties of the last century.

694 JOURNALS, SOCIETIES, AND INSTITUTIONS

Then followed the publications of the British Cartographic Institute
at London, Calcutta, and elsewhere, as well as by French institutions,
which are reported on different pages of this History. The photo-
graphic reproduction processes were carried on extensively and suc-
cessfully, especially at the Military Geographical Institute, Vienna. It
is true that here the methods of procedure employed were, until the
beginning of the seventies, kept more or less secret; thus, while officers
were permitted to copy the formulas for collodion photography and
reproductive processes, nothing was permitted to be published. This
rule was broken by the section chief Ottomar Volkmer and his suc-
cessor Baron A. Hubl. This plan was also followed by Volkmer when
he became director of the Government Printing Office and was con-
tinued by the vice-director, George Fritz. In recent years this activity
has been eliminated. The Government Printing Office at Berlin also
followed this example.

These reports and publications of the great government depart-
ments proved to be important contributions to the general progress
of photography which in turn worked to the great advantage of the
government. In later years government departments for research in
physics included photography among their subjects. We mention only
the Physikalische Reichsanstalt, Berlin; the National Physical Labora-
tory, Teddington (England); analogous institutes in France, including
the Institute d’Optique, Paris, under Director M. Ch. Fabry; and the
United States Bureau of Standards, Washington, D. G, under Director
George K. Burgess, which issues its own Bulletin.

Of the many publications of the U. S. Bureau of Standards we men-
tion only the Standards Yearbook , which contains all the more impor-
tant international standardizations and the monthly reports on com- '
mercial standards. In the “Miscellaneous Publications” of the bureau,
No. 1 14, we find basic investigations on light filters for the production
of artificial daylight (for sensitometry) by Raymond Davis and K. S.
Gibson ( Handbuch , 1930, Vol. Ill, Part 4). This department added
to its activities in the first decade of the present century spectroscopy
and the measurements of the wave length of light (Dr. Burns, Dr.
Meggers, and others) . All these bureaus of research devoted themselves
to the study of normal light sources for photometry and sensitometry
(“Sensitometry,” in Eder, Handbuch, 1930, III (4) , 339).

For institutes of research pure and simple see: Die Forschungs-
institute, ihre Geschichte, Organisation und Ziele, by L. Brauer, A.

JOURNALS, SOCIETIES, AND INSTITUTIONS 695

Mendelssohn-Bartholdy, Ad. Meyer, and J. Lemcke (Hamburg, 1930).

Extremely valuable for the study of photographic science were the
reports of the private industrial research laboratories. One of the first
of these was established at the dry-plate factory of Schleussner, Frank-
furt a. M., from which were published the first investigations of Dr.
Liippo-Cramer. Since 1922 Liippo-Cramer has had the active direc-
tion of the scientific photochemical laboratory of the Deutsche Gela-
tinefabrik A. G., Schweinfurt.

The dry-plate factories of O. Perutz, Munich, of J. Hauff, Feuer-
bach, near Stuttgart (Wiirttemberg), and others added scientific re-
search laboratories to their industrial undertakings. Pre-eminent is the
laboratory in the photographic department of the Berlin A. G. fur
Anilinfabrikation (“Agfa”; see Andresen, ch. lix). No less impor-
tant are the publications of the dyeworks of Meister, Lucius & Briining,
Hochst a. M. (Konig, Homolka, etc., chs. lxiv-lxv). We must
also mention the publications of the Carl Zeiss Works, at Jena, and
those of the Optical Works of Steinheil, Munich; Voigtlander, Braun-
schweig; Emil Busch, Rathenow; Goerz, Berlin; Zeiss-Ikon A. G.,
Dresden, among others.

After the merger of Germany’s great dye works into the Deutsche
I. G. Farbenindustrie A.-G., their research laboratories were also com-
bined. The scientific photographic central laboratory was moved to
Wolfen under the direction of Professor Dr. John Eggert; in 1930
appeared the first volume of the research reports of this central labora-
tory of the “Agfa.”

Important German trade papers, such as the Pbotographische In-
dustrie, Berlin, and Pbotographische Chronik, and Filmtechnik, Halle
a. S., installed private laboratories for the investigation of photographic
materials (Dr. Kurt Jacobsohn, Berlin, and C. Emmermann, Halle) .

Earlier, at the end of the last century, the brothers Lumiere, at
Lyons, published their researches in collaboration with Dr. Alphonse
Seyewetz. The firm Lumiere, Lyons, has published the Agenda for
photography annually since 1905; later Lumiere combined with Jougla
of Paris as Union Photographique Industrielle, which continued the
publication. Its scientific photographic investigations proved highly
valuable; they are recorded in the Jahrbiicher.

The Photographic Research Laboratories of the Eastman Kodak
Company, Rochester, New York, are conducted on an unusually large
scale, having enormous financial resources. George Eastman called a

6 g 6 JOURNALS, SOCIETIES, AND INSTITUTIONS

number of eminent physicists and photochemists to Rochester. The
director of the Kodak Research Laboratories is the English photo-
chemist Dr. C. E. Kenneth Mees, who in 1921 received an honorary
doctor’s degree from the University of Rochester. The extensive and
important research work of these laboratories that the Eastman Kodak
Company published is in part summarized in the Abridged Scientific
Publications from the Research Laboratories of the Eastman Kodak
Company, ; the first volume appeared 19 1 3-14, and it has been published
annually, with a wealth of valuable information. In various parts of
this publication articles by the scientific staff are printed. In the first
volume we find contributions by C. E. Kenneth Mees, P. G. Nutting,
L. A. Jones, J. I. Crabtree, Frank E. Ross, S. E. Sheppard, A. P. H.
Trivelli, and others. Since 1915 the laboratories have also published the
Monthly Abstract Bulletin of the Kodak Research Laboratories , which
contains short abstracts of all pertinent publications in the field of
photography and the allied branches of science and industry. The
Optical Society of America, which also publishes an important journal,
came within the circle of influence of the Eastman Co. The Eastman
Kodak Co. very generously assisted the scientific workers of European
countries which, because of the World War, were entirely cut off from
all technical publications issued outside their own countries by making
available to interested technical circles on the Continent their valuable
original publications and exhaustive references of the war years. For
this aid Continental scientists owe them a lasting indebtedness.

There is also a research laboratory connected with the Kodak Works
at Wealdstone (Middlesex), England, which is directed by Dr. W.
Clark. At Vienna, the research laboratory of Dr. Leon Lilienfeld is in
contact with the Eastman Kodak Works.

COLLECTIONS AND ARCHIVES FOR THE HISTORY OF PHOTOGRAPHY;

DOCUMENTS OF PHOTOGRAPHY

Very little attention was paid by individuals in the last century to
collecting photographic products with an eye to their preservation
for historic reasons. But since the middle of the last century the early
large photographic societies in London, Paris, and Vienna have pre-
served in the archives of their meeting rooms documents for the “His-
tory of Photography.” The Vienna collections were kept at first in
the home of the editor, Ludwig Schrank, of the Zeitschrift der photo-
graphischen Gesellschaft. After his death this publication was taken

JOURNALS, SOCIETIES, AND INSTITUTIONS 697

over by the author for the Graphische Lehr- und Versuchsanstalt, to
which he added his own collection. Other photographic objects of
historical interest are preserved at the Technical College, Vienna, and
in the Historical Museum of Austrian Industry (Technological Trade
Museum), founded by Wilhelm Exner. The Technical Museum for
Industry and Trade was founded in 1918 by Wilhelm Exner, 18 and
its first director was the engineer Ludwig Erhard. The graphic section
was organized by the author with the co-operation of an active com-
mittee. The collections at the Graphische Lehr- und Versuchsanstalt
were under the management of the custodian, Ed. Kuchinka, 19 and
were used in the writing of this History.

Under the direction of the engineer Oskar von Miller the famous
Deutsches Museum was founded, in 1903, at Munich. Rooms 322 and
323 contain a large collection relating to the history of photography.
A short history of photography by Professor Dr. Erich Stenger, pub-
lished in 1929 by the Deutsches Museum, gives some very good his-
torical explanations. This museum has also housed, since 1931, the
collection pertaining to the history of motion pictures donated by
Oskar Messter, of Berlin.

In the Hamburg Museum for Art and Industry are found large
collections of daguerreotypes, first begun by the photographer Wil-
helm Weimar, and at the Book Trade Museum of Leipzig, founded in
1885, photography was included at the end of the nineteenth century.
About this time there was also opened in Leipzig a great museum for
the book trade and literature. There are also historical photographic
collections to be found in some German high schools— Berlin, Dresden
(Krone Collection) .

Of private collections covering the history of photography and
motion-picture photography in Germany that of Dr. Stenger must
be mentioned and also that established by Wilhelm Dost, the recording
secretary of the Photographic Society, Berlin. Dost also wrote a brief
Geschichte der Kinematograpbie (1925) and several articles on his-
torical photographic subjects.

At Paris there are large collections important for the history of
photography at the house of the Societe frangaise de Photographic,
also at the Museum Dantan, as well as that of G. Cromer. In addition
there are photographic collections at some educational institutions and
a collection of the history of cinematography at Lyons. The Niepce
Museum, at Chalon, has been reported earlier in Chapter XIX.

698 JOURNALS, SOCIETIES, AND INSTITUTIONS

In London there is the museum of the Royal Photographic Society
of Great Britain, which is particularly noteworthy. The South Kens-
ington Museum, London, contains not only historical photographic
subjects but also a rich collection of motion picture apparatus. In other
localities in Great Britain there are to be found interesting historical
photographic objects in public and private collections. W e have already
mentioned those relating to Talbot, Hurter and Driffield, and Abney.

The Society of Lithographers and Lithographic Printers, Stock-
holm, owns a large collection appertaining to the history of photog-
raphy and the photomechanical reproduction processes.

In the United States there was added about 1908 a photographic
museum to the Smithsonian Institution, Washington, D. C. The
National Museum at Washington has a rich collection of photographs,
supervised by A. J. Olmsted, chief of its photographic studio; this
museum acquired in 1931 large additions of historic and modem ma-
terial, portraits of inventors and scientists, artistic photographs, also
two motion picture projectors by Woodville Latham, one of which
was constructed in 1895 by the inventor in New York.

The Eastman Kodak Company, Rochester, N. Y., possesses a photo-
graphic museum, with large collections of historical interest, includ-
ing early American apparatus and the inventions introduced by East-
man in the past fifty years.

At the International Photographic Congress in Chicago, 1893, W.
Jerome Harrison recommended the establishment of a collection of
so-called “documented photographs.” Professor Leon Vidal, of Paris,
a member of the committee at the congress, put this idea into effect by
founding the Association du Musee des Photographies Documentaires
in Paris. In 1903 this association owned 80,000 documented photo-
graphs; the classification and registry followed the subject represented
(history, natural science, religion, law, military, art, sports, etc.).

This enormous mass of material necessitated a further division, cor-
responding to the broad field of the applications of photography.
Sometimes under government direction there were gathered collec-
tions of educational diapositives for the study of art history; for medi-
cal use, including Roentgen photography, for anthropology; for
criminal investigations; for the history of civilization; and so forth.

These various collections of “documented photographs,” important
for all fields of scientific research and artistic endeavor, were supple-
mented in modern times by the “documented film.” The collections

JOURNALS, SOCIETIES, AND INSTITUTIONS 699

present an impressive picture of the immense importance of photog-
raphy in all fields of human activities.

ITALY

Scientific life in Italy was nurtured in numerous age-old academies.
We mention here the Academy of Sciences in Florence (founded in
1560), the Academia Secretorum Naturae, of which Jean Baptist Porta
was one of the founders, and the academies at Rome, Venice, Bologna,
and other places. ....

It was in Italy that the “phosphorescent Bologna stone” was dis-
covered, which played a great role in the history of photography. The
discoverer of the light-sensitivity of silver chloride, Beccaria, was a
member of the Academy at Bologna. For daguerreotypy in Italy see
Chapter XXXIII; for photogrammetry in Italy by Porro (1855) see
Chapter LV; for Malagutti see Chapter LVII.

Historical reports on the development of photography in upper Italy
were published by Enrico Unterveger in II corriere fotografico (1922,
No. 12). Wilhelm Dost mentions this in his booklet Vorlaufer der
Photographie (Berlin, 1931, p. 30), and he adds a necessary criticism.

Let us turn to modem photochemistry. At the turn of the nineteenth
century fundamental investigations on the photochemistry of organic
compounds were carried on in Italy by Professor Dr. Giacomo Ciami-
cian (1857-1922), at the University of Bologna. He had studied chemis-
try at Vienna at the university and at the Technical College and was
appointed professor of general and biological chemistry at the Uni-
versity of Bologna. He was one of the most prominent chemists of his
time in Italy and devoted himself to physicochemical work and also
to photochemistry. He was a member of the Vienna Academy of
Sciences. Ciamician’s researches on the chemical action of light on
organic compounds (“Azioni chimiche della luce”), which he carried
on in part jointly with P. Silber, are of the greatest importance. They
are printed in the Mem. Accadem. Bologna, principally from 1900 to
1902, and were also translated into German technical literature ( Photo -
chemie, in the Handbuch, 1906, Vol. I, Part 2). His publications are
registered in Poggendorff ’s biographical pocket dictionary. Ciamician’s
article “Photochemistry of the Future” was translated into German in
191 3 *

Another notable worker in this field was Professor Carlo Bonacini,
at the University of Parma.

7 oo JOURNALS, SOCIETIES, AND INSTITUTIONS

In Florence there was the Societa Fotografica Italiana, a leading
body; G. Pizzighelli was a director until his death. This society pub-
lished a notable journal. Both were dissolved in 1912. The most im-
portant photographic journals of the present time are Progresso foto-
grafico, founded at Milan in 1894 and edited by Professor Namias; II
Corriere Fotografico, founded at Turin in 1905; also La Rivista foto-
grafica italiana founded in 1915 at Vicenza; and finally La gazzetta
della fotografica, founded in 1926 at Palermo.

Photographic societies exist in Milan, Bologna, Turin, and so forth.
There are no schools of photography at present.

Namias was very active in the field of photography and is con-
sidered the most eminent representative of applied photochemistry
in Italy.

Professor Rodolfo Namias (bom 1867), after his college years,
studied technical chemistry at the Polytechnikum at Turin. He com-
menced his career in the Stabilimento Acciaierie of Temi and then be-
came director of the chemical laboratories of the Milan steel foundry.
Later he taught chemistry in the Italian secondary schools, but he left
the educational field and opened in Milan a laboratory for technical
chemical research. Here he established his journal Progresso foto-
grafico, which developed into the most important Italian technical
periodical. In 1913 he enlarged his research laboratory to the Istituto
Chimico e Fotochimico and added an educational laboratory for photo-
chemistry, applied photography, microphotography, and metallog-
raphy.

He has published the following independent photographic works:
Manuale teorico-practico di chimica fotografica (2 vols.); La foto-
grafia in color i, ortocromatismo e filtri di luce; I processi di illustra-
zione grafica; and others.

He has also written many research papers: “Direct Toning of Silver
Images with Copper Ferrocyanide and Ferrous Ferrocyanide” (Phot.
Korr., 1894); “Photochemistry of Mercury Salts” (ibid., 1895); “Di-
rect Positives by Reversal with Potassium Permanganate and Reducing
Negatives with It” (Intern. Congress for Applied Chemistry, Paris,
1900); “Influence of Alkaline Salts of Organic Acids on the Per-
manency of Bichromate Preparations” (ibid., Berlin, 1903). On mor-
dant dye pictures: “Fixation of Coaltar Dyestuffs on Metal Com-
pounds, by Which the Silver Image Is Replaced” (ibid., London,
1909); “Fixation of Colours on Copper Ferrocyanide Images and Ap-

JOURNALS, SOCIETIES, AND INSTITUTIONS 701

plication to Trichromy” (ibid., Rome, 1911); Namias, “Processo di
resinotypia” (Progresso fotografico, 1922) is a resin-pigment method
(Jabrbuch, XXX, 1163).

The photographic reproduction processes were actively employed
in Italy before the end of the last century. In Florence the establish-
ment Fratelli Alinari, founded in 1854, introduced color collotype
printing on power presses about 1891 for their art publishing works,
under Arturo Alinari, who was a pupil of August Albert at the
Graphische Lehr- und Versuchsanstalt, Vienna. Later the firm Danesi
in Rome also produced color collotypes. At present all types of photo-
chromy and of reproduction processes are largely employed in Italy.

The graphic arts, the printing of books, and copperplate engraving
flourished for centuries in Italy. The use of photomechanical processes
in the publishing of photographic art subjects, however, developed
there later than in other European countries. Although there were
famous Italian portrait and landscape photographers at the time of the
wet collodion process and silver bromide gelatine plates were known
early in Italy, in the beginning of the twentieth century the publishers
of postcard views and of art subjects obtained their silver bromide
paper prints chiefly from the large Neue Photographische Gesellschaft,
Berlin. Later there sprang up in Italy factories for silver bromide plates,
films, and paper, as well as extensive motion picture studios; photo-
grammetry and aerial photography for civil cartography and military
purposes have also attained great perfection.

SWEDEN

The history of daguerreotypy in Sweden, where it took hold very
early, is reported in Chapter XXXIII. The subsequent history of pho-
tography in Sweden was treated exhaustively by Dr. Helmer Back-
strom, 20 of Stockholm, in the Nordisk Tidskrift for Fotografi (1919
ff.). See Jabrbuch, XXX, 38, 43, 46, 52, 60.

Information on the Swedish scientist G. Scheutz reported in Chapter
XVII and for the introduction of the diorama into Sweden see Chapter
XXI.

In the fifties Talbotypes were introduced into Swedish studios, and
soon thereafter, the wet collodion process. At about the same time the
first stereoscopic photographs were shown in Stockholm. Noteworthy
is the reproduction by the wet collodion process, ini 856, of the “Codex
argenteus,” Ulfila’s Gothic translation of the Bible, which is preserved

702 JOURNALS, SOCIETIES, AND INSTITUTIONS

at Upsala. Textbooks on photography in Swedish were published by
C. P. Mazer, 1864, C. S. Mylbaus (1874), and others.

The first large Swedish photographic exhibition was held in 1866; 21
it was followed by collective exhibits of Swedish photographers at
Copenhagen (1872) and Vienna (1873).

The first gelatine silver bromide dry plates imported into Sweden
came from Wratten and Wainright, London; they were soon fol-
lowed by other products. Azaline plates, as well as orthochromatic
erythrosine plates from Dr. Schleussner’s factory in Frankfurt a. M.,
came to Sweden in 1887. On balloon photography in Sweden see
Chapter LIV.

In 1888 the Swedish Amateur Photographers’ Society was founded
by T ore Ericsson, teacher of history of art at Stockholm; later a branch
of this society was started at Upsala. In 1 889 professional photographers
were admitted to membership, and the name was changed to The
Photographic Society; it is still in existence. There are photographic
societies in Gotenburg (1888), in Sundsvall (1893), in Lund (1893),
and other places.

The official organ of The Photographic Society, the Nor disk Tid-
skriftfor Foto graft, founded in the same year in Stockholm, is at present
edited by John Hertzberg and Helmer Backstrom.

The Photographic Society in Stockholm is the trustee for awarding
the honor medal founded in 1904 by Claes Adolf Adelskold for meri-
torious service in the field of photography. 22

Major C. A. Adelskold (1824-1907), officer of the engineer corps
for railroad construction, planned and built a great part of Sweden’s
first railroads. He was a prominent amateur photographer, from 1897
an honorary member of the Swedish Photographic Society and often
selected as judge of awards at exhibitions.

The Swedish high schools teach photography and photochemistry.
At the technical college in Stockholm assistant professor and court
photographer John Hertzberg (born 1871) devotes himself to the field
of scientific photography; at Vienna he studied photography, photo-
chemistry, and the technique of reproduction.

At the University of Stockholm the scientist Dr. T. Svedberg teaches
photochemistry. He received the Nobel prize for his research on the
development of the latent light image on silver bromide gelatine plates.
On his work in this field he reported in the Handbuch (1927, II ( 1 ) ,

292 ) published by Luppo-Cramer and the author.

JOURNALS, SOCIETIES, AND INSTITUTIONS 703

A large collection pertaining to the history of photography and the
reproduction processes is at the Lithographtruste, Stockholm.

HOLLAND

For the invention of the magic lantern by the famous Dutch physicist
Huygens see Chapter VII. For Asser and his starch transfer process
see Chapter XCI. Modern photography was well cultivated in Holland.

The oldest photographic society in Holland is: “De Nederlandsche
Amateur Fotografen Vereeniging, Amsterdam. This society is almost
forty-five years old and has rendered great service in the field of
photography. It was formerly almost the only important Dutch photo-
graphic society, although there existed societies in smaller cities. About
1925 there was formed at Amsterdam also the Amsterdamsche A.F.V.,
as well as at Rotterdam, at The Hague, and at Arnhem.

The photographic journal Lux was first published about 1888; later
it was combined with De Camera (founded 1908), published by Eller-
mann Harms & Co., Amsterdam.

The photographic technical journal Focus was established in 1914
and is today ( 1 9 3 2 ) probably the leading Dutch periodical for amateur
photographers. For the professional photographer there is the Be-
drijf sphotographie (since 1928), which is the official organ of the
Nederlandsche Fotografen Patroons Vereeniging. De Fotohandel
and the Fotovreugde must also be mentioned. There are no special
schools for photography in Holland.

BELGIUM

For the inventions of Breyerotypes see Chapter XL. Belgium, at the
time of Van Monckhoven, was prominently active in the field of
photography (see Chapter LIX). The Association Beige de Photo-
graphic, founded at the end of the eighties, was an influential photo-
graphic society; it published a valuable periodical, the Bulletin de l’ As-
sociation beige de photo graphie, of which the first volume appeared
in 1889. Another still older Belgian photographic journal was the
Bulletin beige de photographie, which was first published at Brussels
in 1861. The Photoclub de Belgique published the periodical Bulletin
from 1896.

Scientific photography also was cultivated in Belgium.

DENMARK

The earliest photographic society in Denmark was Den fotografiske

7 o 4 JOURNALS, SOCIETIES, AND INSTITUTIONS

Forening, founded January 20, 1863. Beginning in 1865, the society
published Den fotografiske Forenings Tidende, but the society and its
organ lasted only a few years.

On April 5, 1879, the Dansk fotografisk Forening was founded; it
still exists. In October, 1879, the Beretninger fradansk fotografisk
Forening appeared, first quarterly, then monthly, continuing after
January 1, 1903, as Dansk fotografisk Tidskrift.

A course in photochemistry was established at the technical college
of Copenhagen in 1912, broadened to include scientific photography
in 1914, and merged with the independent photochemical laboratory
at the same college in 1917. A full professorship of scientific photog-
raphy was instituted in 1919, now under the direction of Professor Dr.
Chr. Winther.

SWITZERLAND

In Switzerland many eminent men devoted themselves to the de-
velopment of photochemistry and photography. We have already men-
tioned the activities of the learned professor Konrad Gesner at Zurich;
the inventor of the first chemical photometer, Saussure, at Geneva; and
the photochemical work of the Geneva scientist Senebier. 23 For Chr.
Friedr. Schonbein see Chapter XLII.

The invention of daguerreotypy soon came to Switzerland. The
first daguerreotype from Paris was sent to the painter and copperplate
engraver Johann Baptist Isenring (1796-1860) at St. Gallen, where
he was established as an art publisher.

Isenring was a skilled artist who published a series of aquatint views
of towns and often colored his copperplate prints. Shortly after da-
guerreotypy became known, he bought a Daguerre-Giroux camera
in Paris; he photographed architectural subjects as early as December,
1839. The light in the Swiss Alps, sometimes very actinic, enabled him,
in March, 1 840, to take portraits with the optically weak apparatus of
the first daguerreotype cameras. Although they have not been pre-
served, these early portraits are fully described in the St. Gallen news-
papers of that time. The pictures were taken in sunlight with long
exposures, showed sharp, deep shadows, and the eyes of the sitter were
indistinct or appeared closed, owing to the long exposure, wherefore
the copperplate engraver Isenring retouched them on the silvered
copperplates. Isenring, who was adept at coloring copperplate prints,
conceived the idea of coloring daguerreotypes also. In this he was

JOURNALS, SOCIETIES, AND INSTITUTIONS 705

very successful, and his work attracted public attention. He exhibited,
from September to November, 1840, many examples of his light-
pictures at Zurich, Munich, Augsburg, Vienna, and in July, 1841, at
Stuttgart and Munich. At this time Isenring established the first Helio-
graphic Atelier for daguerreotypy at Munich, with great success, ex-
amples of his work being exhibited at the gallery of the Munich Art
Society.

In July, 1841, Isenring returned to St. Gallen, where he arranged an
exhibition of daguerreotypes at his shop, among them, according to
the Munich newspapers of October 8, 1841, daguerreotypes 3x4
inches in size of the colorful scenes at the October fair there, made in
one second (undoubtedly with a Petzval-Voigtlander lens). See also
the remarks about the first instantaneous daguerreotype exposures in
Chapter XXXII.

When, in 1 843, many other daguerreotypists entered the field, Isen-
ring returned to St. Gallen, where he remained in very modest circum-
stances until his death. Isenring’s house, in which the first photographic
studio in Switzerland was established, no longer exists. A few years
ago the city of St. Gallen honored his memory by naming a road after
him, “Isenring- Weg.”

Dr. E. Stenger has given us an interesting historical study of the
Daguerreotypist J. B. Isenring in an illustrated booklet, published pri-
vately at Berlin, 1931, from which the above biographical details are
taken.

From these beginnings photography was developed as time went on
by the introduction of the calotype, the collodion and the gelatine
silver bromide processes; all were used especially for Alpine photog-
raphy. The growth of the photographic industry kept pace with this.

In 1897 a department was established at the municipal trade school
at Zurich for training apprentices in photography; R. Ganz was the
director.

In Switzerland the first course in scientific photography having both
lectures and practical demonstrations, was started toward the end of
the nineteenth century at the technical college at Zurich under Profes-
sor Dr. Barbieri, who died in 1926, 75 years old.

Camera , an illustrated monthly journal founded in 1921, published
by C. J. Bucher A.-G., Luzerne, and edited by Adolf Herz, stands out
as the Swiss photographic periodical which has won an important place
as far as artistic and scientific photography is concerned.

7 o6 journals, societies, and institutions

RUSSIA

To give an adequate account of the development of photography
in Russia is impossible, owing to lack of space and because the recent
political changes have made it extremely difficult to obtain the neces-
sary facts and data for such a survey. We must therefore be content
to record only the characteristic events in the development of photog-
raphy in Russia.

The Imperial Russian Academy of Sciences at St. Petersburg (Len-
ingrad), founded two hundred years ago by Peter the Great, who
housed it in a magnificent building, turned its attention at an early date
to the chemical action of light, as demonstrated by the prize competi-
tion which it held in 1 804 on the “Nature of Light,” which led to the
award to Link and Heinrich for their basic dissertation on the subject
(see Chapter XVI) . This was printed in German at St. Petersburg, in
1 808, and gives a clear and splendid review of the knowledge of photo-
chemistry at the beginning of the nineteenth century.

Peter the Great founded the academy upon the advice of the famous
German scientist G. W. Leibnitz. The plan of organization was drawn
by Leibnitz, who took the older academies at Paris, London, and Berlin
(of the latter he was president) as his model. The Academy of Sciences
at St. Petersburg was not formally opened until after the death of Peter
the Great, when it was opened by his successor the Empress Catherine,
January 7, 1726. The Russian czars zealously fostered the Academy of
Sciences, and the present government continues it as the Soviet Acad-
emy of Sciences in Leningrad. The stately edifice of the Academy of
Sciences at St. Petersburg 24 included not only studios and laboratories
for scientific work and investigations but also living quarters for the
academicians, who were appointed by the czars.

Gottfried Wilhelm Leibnitz (1646-1716), the famous scientist who
induced Peter the Great to found the academy, was enabled to accom-
plish this owing to his connections at the Russian and the Prussian
courts. Leibnitz was appointed a member of the St. Petersburg Acad-
emy, which at the beginning numbered among its members the French
astronomer Jos. Nic. Delisle, the mathematician Joh. B. Bernoulli, and
the German philosopher of the Leibnitz school Georg Bemh. Bilfinger.
Later, in 1733, the famous German mathematician Leonhard Euler was
also called to the academy, which always kept up pleasant relations
with German scientists.

We must also mention here the Academy of Arts and the Society

JOURNALS, SOCIETIES, AND INSTITUTIONS 707

for the Advancement of the Graphic Arts at St. Petersburg. Here the
graphic arts were cultivated, to which soon was added, in accordance
with the times, photographic technique.

On the “iron tincture” produced by the Russian Chancellor Bes-
tuscheff in 1725 by the action of light see Chapter VIII. See also
Chapter XVII on Brandenburg and on the work of Von Grotthuss;
Chapters LXXXV and LXXXVI on Jacobi; and Chapter LXXXVIII
on Gustav Re.

The correspondence mentioned in footnote 14 of Chapter XIX
proved the great interest shown by the Russian government in the ear-
liest work of Niepce.

Photography was closely watched in St. Petersburg by the court
authorities from the invention of the daguerreotypy in 1 8 39, and ex-
periments were ordered to be made after Daguerre’s directions, at first
from landscapes and architectural subjects.

The traveling daguerreotypist Josef Weninger, of Vienna, came
to St. Petersburg in August, 1841, by way of Stockholm and Finland
(as Backstrom relates), and he was the first to bring a Petzval portrait
lens and daguerreotype plates prepared after the more sensitive Vienna
method, thus opening the road in Russia for the practice of daguerreo-
typy and portrait photography.

When Talbot’s calotype process made its appearance there were al-
ready in Russia amateur photographers, for instance, the Prince Paul
Trubetzkoy at Odessa, who in 1851 made sixteen paper negatives,
which he exhibited at the Moscow Photographic Exhibition of 1889,
as reported by Scamoni in his description of the exhibition. Subse-
quently the wet collodion process was adopted. In 1851 H. Denier, the
Imperial Court photographer, who later became very famous, estab-
lished himself in St. Petersburg; he played a leading role there for
several decades and also received high awards at the Vienna Interna-
tional Exhibition of 1873 for his artistic accomplishments in photog-
raphy.

In 1859 the photographer Migursky published a textbook on pho-
tography in Russian, which had a large sale. There existed also an
old Russian technical journal, Photograph, which was edited about
1865 by Friebes.

The development of portrait and landscape photography, as well
as amateur photography, in Russia was rapid and considerable. The
Russian general Count Nostitz of St. Petersburg was an earnest amateur

708 journals, societies, and institutions

photographer about the middle of the last century. He participated in
a campaign against Schamyl, the last independent chief of the Cir-
cassians, who was defeated in 1859. At the time of the collodion process
Count Nostitz took photographs in the Caucasus of the country and of
its inhabitants. At the Moscow Photographic Exhibition of 1889 he
showed fifty-two photographs, representing portraits of members of
the imperial family, castles, battleships, groups and landscapes of the
Crimea and of Little Russia. Some of these were shown to the author
by Count Nostitz when he visited Vienna.

The seasonal change of light conditions at St. Petersburg prompted
experiments with artificial lights in photographic studios. The photog-
rapher Lewitsky opened in 1881 a portrait studio (after Liebert’s sys-
tem, Chapter LXXIII) equipped with such strong arc lights that he
was enabled to take portraits on wet collodion plates in four seconds.
Dutkiewicz, in Warsaw, conducted at about the same time a similar
business in his night studio and praised the easy method, since electric
light, acting as a constant source of light, obviated errors in the length
of exposure.

Gaston Braun, of Paris, was called to St. Petersburg in 1880 to re-
produce paintings at the Hermitage picture gallery. Braun had at that
time taken the first orthochromatic photographs of paintings with
eosine wet collodion plates for art dealers and had reproduced them
by the pigment printing process. Many of these art prints appeared in
the art stores at St. Petersburg and at Paris.

Gelatine silver bromide dry plates were at first imported from
London to St. Petersburg, seemingly by an arrangement with War-
nerke, who kept up an active connection with London, Brussels, and
St. Petersburg.

The first Russian gelatine dry-plate factory was erected by A. Felisch
in 1881. Then Wamerke, with Sresnowsky, established a gelatine
silver bromide plate factory in St. Petersburg, to which he later added
the manufacture of gelatine silver chloride papers.

In Moscow also photography received a good deal of attention,
which is proved by the great photographic exhibition of 1 889, under
the protection of Archduke Alexis Alexandrowitsch, where there was
also a historical section (Phot. Korr., 1889, pp. 199, 243).

The photomechanical processes were intensively cultivated, es-
pecially at St. Petersburg. On electrotyping, photoelectrotyping, and
so forth we have reported in Chapter LXXXV. Photolithography,

JOURNALS, SOCIETIES, AND INSTITUTIONS 709

collotype, and zinc etching developed parallel with the industry in
other countries. It is noteworthy, in reference to the general interest
in the photographic processes in Russia, that A. Jedronoff, a naval offi-
cer, worked at collotype from 1872, but he applied the chromated
gelatine, not in the usual manner to glass plates, but to copper plates.
In 1885 he printed his collotypes on a typographical press (“Typo-
graphischer Lichtdruck,” Phot. Korr., 1885, p. 80).

The tempestuous political conditions during the czarist monarchy
and the large amount of propaganda material, printed mostly in under-
ground printing shops, caused the most rigorous supervision of all print-
ing presses by the government, which was a great hindrance to the
spread of the technique of reproduction.

Officially photography was advanced especially by the Imperial
Russian Technical Society at St. Petersburg, which consisted of several
sections, each of which dealt with one of the different technical fields
as its subject proper.

Urged by Wamerke, the fifth group of the society, “The Photo-
graphic Section,” was established in 1880. It became the important
center of the photographic industry and of the various branches of
industrial, artistic, and scientific photography. From here were pub-
lished the reports of the “Office for the Production of Government
Papers,” St. Petersburg, and of the cartographic section of the General
Staff, which had in its service studios and efficient reproduction tech-
nicians. Here were produced the microphotographs of the botanical
section of the university (1884). Constantin Schapiro, appointed in
1880 special photographer to the Academy of Fine Arts, distinguished
himself especially in the field of portrait photography and made many
recommendations, on which Scamoni reported in Phot. Korr. of 1883
and later.

The government’s central institution for the graphic arts was the
“Imperial Russian Office for the Production of Government Papers,”
St. Petersburg. Here were produced the Russian bonds, ruble notes,
stock certificates, and valuable printed matter of all sorts; but artistic
printing and book illustrations were not neglected. 25 The photographic
processes found an eminent representative there in the person of
Scamoni.

Georg Scamoni (1835-1907) was born in Wurzburg, Bavaria, the
son of a town councillor. He learned lithography, was employed at
the printing house of C. Neumann, Frankfurt a. M., and was called

7 io JOURNALS, SOCIETIES, AND INSTITUTIONS

in 1863 to the Office for Production of Government Papers at St.
Petersburg. He introduced there with great success photolithography,
collotype, gravure, and so forth, acted as chief of the section until
1898, was overwhelmed with honors, and died at St. Petersburg.

This Office for Production of Government Papers was of great im-
portance at the time of the Russian monarchy. Prominent statesmen
such as Prince Golitzin acted as president, and the famous Minister of
Finance Count S. J. Witte kept this government printing office under
his personal supervision. The demand for the product of this depart-
ment frequently became so great that the private art printing concern
of Policke and Wilborg, St. Petersburg, was often given emergency
orders for printing.

Bruno G. Scamoni, son of Georg Scamoni, who received his train-
ing at the Graphische Lehr- und Versuchsanstalt, Vienna, became
technical director of the printing firm of Policke and Wilborg. To
this establishment Karl Albert was called from Vienna, in 1903, to
install Klic’s heliogravure; he remained there until 1909. After the
Russian revolution the firm lost its importance. Director Scamoni had
to leave Russia and went to Berlin by way of Finland.

Before the World War the Russian printing office kept in close
touch with the government printing offices in Berlin and Vienna. Con-
ferences of the managers of these institutions were held annually at
one of three capitals for discussing preventive measures against counter-
feiting.

The World War brought these meetings to an end, but in 1930-31
the League of Nations resumed the conferences. An international
convention for the prevention of forgery and counterfeiting of govern-
ment securieties was called and joined by sixteen countries. The first
meeting took place on March 4, 1931, at Geneva, under the pro-
tection of the League of Nations. The board of examiners is located
at Vienna.

In 1886 the Russian printing office called the Vienna phototechni-
cian and engineer A. Nadherny to be chief of the engraving section.
Nadherny, in 1 890, called to St. Petersburg the copperplate engraver
Gustav Frank and in 1891 the photochemist Wilhelm Weissenberger; 28
both were Austrians. The office employed all modern reproduction
methods, including three-color process printing, with splendid results.
Nadherny returned to Vienna in 1901 as director of the securities
printing department of the Austro-Hungarian Bank (now National

JOURNALS, SOCIETIES, AND INSTITUTIONS 71 1

Bank). Frank resigned in 1913, having been appointed state councillor,
and went to Leipzig, where he joined Schelter and Giesecke, manu-
facturers of security and banknote papers. Weissenberger remained
in St. Petersburg until he was able to leave Russia in 1920, when he
went to Germany.

Photographic education was available in old Russia in various places.
The Imperial Russian Technical Society at St. Petersburg included
in its section for photography a course, with lectures and demonstra-
tions, which for many years before the World War rendered great
service to industry and science. But it was much later that the teaching
of photochemistry as a separate subject was introduced into the cur-
riculum of colleges.

The first chair for photochemistry in Russian colleges was filled by
Professor J. Plotnikow a few years before the World War, at the
University of Moscow. Here Plotnikow began an active career in the
scientific field, which the Russian Revolution abruptly terminated.
The history of Plotnikow’s professorship, as described in the preface
of his book Allgemeine Photochemie (Berlin-Leipzig, 1920) might
well be cited in this work, which has set itself the task not only of
the narrower technical history of photography but also of presenting
the history in relation to the course of events during its development. 27

Plotnikow was born on December 4, 1878 (still living in 1932), in
one of the central regions of Russia, the son of a well-to-do engineer
and architect. After leaving college in 1897, he studied mathematics
and physics and was graduated from the University of Moscow in 1901.
From there he went to Leipzig in order to study physical chemistry
under W. Ostwald (190 1-7), where he received a doctor’s degree in
philosophy. After the retirement of Professor Ostwald, Plotnikow
left Leipzig and returned to Moscow, where he taught photochemistry
at first as lecturer in 1910, as assistant professor in 1912, and as full
professor in 1916. In 1913 he equipped at his own expense the first
Russian photochemical laboratory. He owned a large country estate,
where he spent his summer vacations. He was discharged in 1917 by
the Kerensky government, and his chemical laboratory was destroyed.
He retired to his country place, which also met destruction by the
peace-loving peasants, who were ordered by the government to de-
stroy it.

Soon after Plotnikow had found a position in the scientific photo-
chemical laboratory of the “Agfa” at Berlin, he was called to the Zagreb

7 I2 JOURNALS, SOCIETIES, AND INSTITUTIONS

University (Jugoslavia). This institution was established in the early
days of the monarchy and was housed in beautiful buildings. 28 When
taken over after the World War by Jugoslavia, it was enlarged by
the addition of a technical faculty, and Plotnikow was appointed pro-
fessor of physics, chemistry, and photochemistry. He became director
of the physicochemical institute and is now the leading scientific repre-
sentative of photochemistry in the Balkan States (Phot. Korr., 1929-
30; and the Jahrbiicher) .

Better than the photochemical institute at Moscow, fared the indus-
trial government printing institutions and the government printing
office for securities, because the Soviet Union required them as much
as the czarist government. The former imperial printing office was
moved, with its machines and equipment, to Moscow and continued
in full working order, while the paper factory connected with it re-
mained in Leningrad. The military cartographic institute at Leningrad
was continued, with most of its staff, after the revolution, but was
transferred to Moscow and placed under the People’s Commissar for
the Army.

According to the reports of the embassy of the Union of the So-
cialist Soviet Republics at Vienna (1931) there are located at Moscow:
( 1 ) The Printing Office for the Production of Government Securities
(Gosznak); (2) The Military Photographic Institute (Rewwensoet);

(3) The Government Publication Office of the Soviet (Gosizdat);

(4) The All-Russian Society of Photographers (W.O.F.).

The Soviet authorities established various photographic sections in
the government service— for instance, at the Aeronautical Institute
(section for aerial photography), 29 at the Geological Institute (geo-
logical committee), 30 and at the Technological Institute and the agri-
cultural section connected with it, all of which are located at Leningrad.

Occasionally, when the necessity arises, photography is employed
by the different scientific institutes at Leningrad, 31 in Moscow, and at
the universities of Irkutsk, Kasan, Minsk, Odessa, 32 Tomsk, and the
Ukrainian Chamber of Weights and Standards at Charkow. 33

After the revolution considerable attention was paid to photography
in Russia. In 1917 a Government Photographic College was established,
and Popowitzky, the former chief of the Government Printing Office
was appointed rector (president). Probably “college” does not cor-
respond to the meaning the title implies in Germany or elsewhere, but
it offers an opportunity for the study of and development in the field

JOURNALS, SOCIETIES, AND INSTITUTIONS 713

of photography. A “Technikum” for motion picture photography
(1927) and a special institute for optics were established under the
direction of Professor Rostjestvenski.

The publishing house Ogoniok (1929), in Moscow, publishes the
journal Soviet-Photo; one of its issues describes the organization and
activities of a photographic union in Russia.

The Society for Cultural Relations between the Soviet Union and
foreign countries, which fosters intellectual interchange, is located
at Moscow. The academies of sciences at Vienna, Berlin, and elsewhere
exchange their scientific publications with those of the various Russian
academies, universities, scientific bodies, and technical educational in-
stitutions.

From the information at hand, it appears that the Soviet government
controls all these institutions and, of course, also those touching on
and dealing with photography; even the distribution of photographic
cameras to labor organizations is a governmental function. Private
activity in the field of photography, we suppose, is very difficult, be-
cause the economic organization of the Soviets has taken over the trade
in everything, which includes, naturally, photochemical supplies,
cameras, and accessories. Amateur photography in Russia is practically
extinct, owing to the risk the photographer incurs, in awakening dis-
trust of political motives and having to face awkward consequences.

Notwithstanding these regrettable circumstances, we must acknowl-
edge and appreciate the work and results brought to us by the official
Soviet scientific and technical journals, which are full of unusually
splendid photographs, reproductions, and scientific research.

JAPAN

According to a report 34 in the Deutsch-japanische Post, Yokohama,
August 19, 19 1 1, the draftsman and painter Renjyo Shimooka (1823-
1914) was the first native of Japan to carry on the art of photography
in the Far East. He still lived in 1911, 88 years old, and he related
how with a great deal of trouble and difficulty he had seen how
photographs were made when an American warship arrived in the
harbor. He succeeded in opening a photographic studio in Yokohama,
but encountered the superstition of his countrymen that having
one’s picture taken meant an early death. His first customers were
sailors from foreign warships, who enjoyed being photographed in
company with Japanese girls. Gradually the people overcame their

7 i 4 JOURNALS, SOCIETIES, AND INSTITUTIONS

prejudices, took pleasure in being photographed, and many studios
made their appearance in Tokyo, Yokohama, and all other large cities,
probably as early as the sixties of the last century.

The Japanese All Kanto Photographic Association arranged in 1928
the erection of a memorial tablet in Szimoda Izu, the native town of
the pioneer in photography Renjyo Shimooka ( Japan Photographic
Annual, 1928-29, p. 1).

Until the eighties the wet collodion method dominated in Japan.
Gelatine silver bromide plates were introduced into Japan largely
through the influence of the English amateur photographer and scien-
tist W. K. Burton (1835-99). He lived in London in the eighties and
wrote a number of articles and books, mostly on silver bromide emul-
sions. 35 He was by profession a sanitary engineer and was called in
1887 by the Japanese government to the Imperial College at Tokyo
as professor of sanitary engineering. His excellent knowledge in the
field of applied photography undoubtedly had something to do with
his appointment. He had at his disposal in Tokyo two large photo-
graphic studios, where native and foreign visitors were always given a
wholehearted reception. The Englishman T. B. Blow told this author
that during several visits to Japan (1896 and 1898) he was given the
use of the available facilities for his photographic work. Burton also
introduced platinotypes into Japan and was a silent partner in the first
Japanese collotype establishment of Ogawa, which had attained much
commercial importance at the end of the last century. Burton owned
a rich collection of large negatives of Japanese scenes and photographs
taken in Formosa. He attempted also to produce gelatine silver bromide
plates in Japan, but encountered great difficulty in finding suitable
glass. Japanese houses had at that time only paper windows, and the
small amount of imported window glass was of the cheapest quality
and unfit for the manufacture of dry plates. In addition he had to over-
come trouble in drying the emulsion-coated plates during the hot
weather and immediately following the rainy season, when the atmos-
phere is saturated with humidity. Burton therefore made the dry plates
needed for his own use, but never manufactured any for the trade.
Burton died in Tokyo, and George E. Brown wrote his obituary
article in the British Journal of Photography (1899, p. 603).

At first dry plates and other photographic requirements were im-
ported by Japan from England, which had a monopoly of this trade
for years, but later the United States has shared in the trade.

JOURNALS, SOCIETIES, AND INSTITUTIONS 715

Photography has been a subject in the curriculum of the Japanese
high schools for a long time; for instance, Professor Yasugi Kamada
lectured on photochemistry at the university at Senday from 1916 un-
til 1922, when a course in photography and reproduction was estab-
lished at the Tokyo Polytechnic College (Tokyo Kogei Gakka), to
which Professor Kamada was appointed.

A medal for services in the field of photography shows a picture
of Fujiyama penetrating the clouds, the high volcanic cone on the
Japanese Island of Nippon. It is considered a national shrine and as
such a favorite motive for Japanese art.

In 1930 the medal was awarded by the Friends of Photography,
presided over by Professor Y. Kamada, to this author. The mountain
on this medal was modeled from a photograph by Kamada, who had
taken it with infrared light filters on neocyanine plates at a distance
of 68 kilometers (42 1 / 2 miles).

The translation of the text on the reverse side of this medal reads:
“As a remembrance of the seventy-fifth birthday of Prof. Dr. J. M.
Eder, in gratitude for and appreciation of his great services in photog-
raphy and the art of printing, his Japanese colleagues respectfully
present him with this medal of honor, Tokyo, December, 1930.”

Only very lately were modernly equipped factories for silver bro-
mide gelatine plates and papers of all kinds established: the Oriental
Photo Industrial Co., Ltd., Tokyo (founded in 1920); the Tokyo Dry
Plates Co., Ltd., Tokyo, Kampan Kabushiki-Kaisha; Nihon Photo In-
dustrial Co., Ltd.; and the Asahiphoto Industrial Co., Ltd., which was
started in 1908. The firm Rokuosha, among others, also manufactures
cameras. Because of the great number of professional and amateur
photographers in Japan it is easy to understand that there exist
many societies. The best known is that of the professional photog-
raphers, Nihon Shashinshi Rengo Kyokai. A number of photographic
societies united in arranging the first Japanese exhibition of amateur
photography, in 1927, at Tokyo and Osaka, which was called the Inter-
national Photographic Salon. 38 Then followed exhibitions of “Japanese
artistic photographs.” Since 1911 exhibitions by the Tokyo Photo-
Research Society and by the Manchurian Artistic Photographs group
show annually the result of their work. 37 The Osaka Industrial Ex-
perimental Station works for industrial purposes. In Tokyo was found-
ed, in 1929, the Amateur Cinema Club. The Tokyo Scientific Photo-
graphic Society was founded in 1926 and numbered more than 100

7 i6 journals, societies, and institutions

members in 1931 (president, General Lieutenant Hitoshi Omura; di-
rector, Professor Y. Kamada).

The Japanese government gave special attention to photography
at the beginning of this century and sent painters, photographers,
phototechnicians, and scientists to Europe to be educated in the
field of photography. A number of these studied at the Graphische
Lehr- und Versuchsanstalt, Vienna— among them Takheri Kamoi, now
at the University of Tokyo, Major Hitoshi Omura, the painter Seiichi
Oka, and the cartographer K. Ogura, who was detailed to the Military
Geographic Institute, Vienna, and also visited the section on reproduc-
tion of the Graphische Lehr- und Versuchsanstalt. He returned to
Japan before the outbreak of the Russo-Japanese War (1904) and in-
troduced map printing by means of photoalgraphy at the Military Geo-
graphic Institute, Tokyo, with the result that the Japanese army and
navy in the above-mentioned war were equipped with excellent maps
of this kind.

Ogura sent to this author in 1 904 an original war map from the theater
of war in Manchuria, printed on thin waterproof paper by algraphy,
which presents very precise execution ( Jahrbuch , 1908, p. 132). An
example of these Japanese war maps of 1903-4 is preserved in the
Technical Museum for Industry and Trade, Vienna. Ogura was chief
of the Military Geographic Institute at Tokyo until 1928.

The Japan Photographic Annual has been published since 1925 by
the Asahi Shimbun Publishing House, Tokyo and Osaka. The preface
is in English, the balance in the Japanese language and script, and it is
richly illustrated.

In portrait and landscape photography the production of postcard
views and the photomechanical illustration of books and periodicals in
halftone, collotype, rotogravure, etc. Japan has become independent
of the outside world.

As far as the author is able to ascertain, Japan seems to be superior
to China in the field of modem illustration. The Academia Sinesica at
Nanking founded there the Metropolitan Museum of Natural History,
which since 1930 has issued a journal printed in English and Chinese
script by means of the earlier graphic processes (lithography, etc.) . The
illustrations are not particularly noteworthy examples of photography.

Chapter XCVII. supplement to the chap-
ters ON DAGUERREOTYPY AND CINEMATOG-
RAPHY

A. To Chapter XXIV, p. 228: The quotation from Liebig, Cornbill
Magaz. (1865) XII, 303, is taken from an address of Liebig that he
made March 28, 1 865, at a session of the Academy of Sciences at Mu-
nich; it is reprinted in Reden und Abhandlungen von Liebig, Leipzig,
1874, p. 296 (see E. Stenger, Phot. Korr., 1931, p. 225).

B. To Chapter LXXI, p. 516: Among the pioneers in motion
picture photography the Frenchman Le Prince is mentioned. A com-
mittee was formed at Leeds, England, to honor his services and to pre-
serve his memory. The committee requested subscriptions for a “Me-
morial to L. A. A. le Prince, Father of Kincmatography,” to be affixed
to his residence at Leeds. The inscription reads: “Louis Aime Augustin
le Prince had a workshop on this site, where he made a one-lens camera
and with it photographed animated pictures. Some were taken at Leeds
Bridge in 1888. Also he made a projecting machine and thus initiated
the art of kinematography. He was assisted by his son and by Joseph
Whitley, James Wm. Longley, and Frederic Mason of Leeds. This
tablet was placed here by public subscription.”

L. A. A. le Prince (1842-90) was the son of a French officer; he
studied chemistry and physics at Paris and Leipzig, and painting under
Billeuse at Paris, where he met the Englishman John R. Whitley, who
invited him to Leeds, where both devoted themselves to painting. Le
Prince married Whitley’s sister and settled at Leeds. In 1881 he went
to the United States in order to stage panoramic paintings in New
York, Washington, and elsewhere. There he learned of Muybridge’s
serial photographs, which at that time attracted great attention. This
led him to construct a camera for the production of motion pictures,
which he patented on January 10, 1888 (U. S. patent No. 376,247),
describing it as the “method of, and apparatus for, producing animated
pictures.” On his return to Leeds in 1887 he completed the practical
construction of his apparatus, and he patented it in England (November
16, 1888) as well as in Austria and other countries. In 1889 he used
long perforated and transparent strips of film.

On a business trip to Paris, in 1 890, Le Prince visited friends in Di-
jon, and he was last seen on September 1 6, 1 890, boarding the Dijon-
Paris train. Since that time he has disappeared completely, and his

SUPPLEMENT

718

family, who engaged a number of French and English detectives, never
was able to find a trace of him again. His heirs and friends had seen his
presentations, and some knew all the details of the construction of his
apparatus, but no one was able to utilize it practically.

C. To Chapter LX VI, p. 489, and Chapter LXXI, p. 518: Thomas
Alva Edison (1847-1931) was bom at Milan, Ohio. His father came
from an old Dutch family of millers, who had emigrated a hundred
years earlier. He had to help earn his living when eleven years old by
selling newspapers on railroad trains. Then he became a telegraph
operator, but his mind was always occupied with inventions, and he
made several successful inventions in the field of telegraphy.

In 1 876 he started a laboratory at Menlo Park, New Jersey, near
New York City, where he worked on the improvement of the tele-
phone. Two years later he invented his phonograph, which made his
name known throughout the world. In 1879 he invented the carbon
filament incandescent lamp; in 1881, the Edison dynamo; at that time
he began the erection of powerhouses for electric illumination. In 1 887
Edison erected large works, mostly for research and testing purposes,
at West Orange, New Jersey. We are interested here only in those of
his numerous inventions which his successful activities developed in
the field of photography.

The various attempts of Muybridge and others to produce photo-
graphic serial pictures did not escape Edison’s attention. He conceived
the idea of constructing a film camera for serial instantaneous pictures,
and in 1 889 he entrusted the Eastman Kodak Co., Rochester, with an
order for a “motion picture camera,” for which he furnished complete
working plans. This camera (kinetograph) Edison equipped with
films especially manufactured by the Eastman Company. The box in
which the observer viewed the living pictures he called “kinetoscope.”

For a long time Edison kept the construction of the kinetoscope
secret. Later it became known that in the final models the intermittent
motion of the film was obtained by friction (C. Forch, “Edison and
His Connection with Cinematography,” Kinotecbnik, 1931, p. 397 ) .
Edison applied for patents on these apparatus on August 24, 1891. The
patent on the kinetoscope was granted on March 14, 1893, but that on
the kinetograph was strongly contested, and Edison was forced to
divide this patent into three parts; on these, patents were not granted
until 1897. It is noteworthy that Edison’s kinetoscope was arranged
for only a single observer to view the subject— a peep box. The posi-

SUPPLEMENT 719

rive film was continuously moved in front of the window in the box
by an electric motor. A continuous rotating disk, with slits, exposed
each image of the film to the observer for a short time.

The kinetoscope films, easily obtainable on the market, prompted
further experiments. We have mentioned that Le Roy, in 1894, pro-
jected motion pictures on a wall with such films by means of a special
apparatus of his own. On May 20, 1895, Major Woodville Latham also
presented such projections of kinetoscope films with his “panopticon.”
A few months earlier the Lumiere brothers in Lyons had taken out a
French patent on their “cinematograph.” Thomas Armat had also
shown film projections in Washington, D. C. Along the lines of these
experiments Edison produced his “vitascope,” which was used for
kino-projection at New York City in April, 1896.

Later Edison combined these projection apparatus cleverly with
his phonograph (“kinetophone”) and thus produced the first practi-
cable, though imperfect, tone film. The kinetoscope and the kineto-
phone could be seen for some time in all the great cities of the world,
but they were displaced by Lumiere’s cinematograph and other modem
apparatus.

Edison’s work in this field was without doubt a decisive step along
the road of modern motion picture technique. He died on October 18,
1 93 1 , at West Orange, New Jersey.

Biography of josef maria eder, by hinricus

LUPPO-CRAMER

Josef Maria Eder, son of Josef Eder, a judge of a county court, was
bom March 16, 1855, at Krems on the Danube. His mother, Caroline,
was the daughter of Ludwig von Borutski, legal advisor (district cap-
tain and judge) of Tulin, Lower Austria. Ludwig von Borutski was of
Polish origin, his family having emigrated after the third partition of
the Kingdom of Poland. Eder attended the old Piarist preparatory
school at Krems from 1 8 64 to 1 8 7 2 ; after that he entered the University
of Vienna. There he specialized in the study of the natural sciences. At
the same time he pursued studies at the technical high school, where
he came in contact with the pioneers of photography, such as the Li-
brarian Martin, Professor Pohl, Professor Homig, Angerer, and others.
In addition to these important professional photographers, there were
also a number of amateur photographers in Vienna, among whom was
Captain Victor Toth, who later married Eder’s sister Caroline.

While in Vienna, Eder published several works on chemistry; name-
ly: Die Bestimmung der Salpetersaure (1876); Untersuchungen iiber
Nitrozellulose; “Analysen des chinesischen Tees,” in Dingler’s, Poly-
technisches Journal; Bleicben von Schellack; etc. While at the univer-
sity he specialized in the study of the chemical foundation of photog-
raphy and investigated the double salts of cadmium bromide and iodide
in their relation to negative collodion. With Toth he announced a lead
intensifier and investigated the methods of dyeing photographic silver
plates with the aid of ferricyanides, which were later to become very
important.

About that time the Photographic Society of Vienna held a com-
petition to further the study of the chemical principles underlying color
photography, which undoubtedly had a determining influence on the
course of scientific study later pursued by Eder. Eder’s treatise, Vber
die Reaktionen der Chromsaure und Chromate auf Gelatine, Gumrm ,
Zucker und andere Substanzen organischen Ursprunges in ihren Be-
ziehungen zur Chromatphotographie (1878) was awarded the first
prize in the competition. This work evidences a thorough understand-
ing of the technique of reproduction and is a classic in its field.

For a time Eder worked in the Austrian State Mining Laboratory

JOSEF MARIA EDER 721

under the chief mining engineer, Pattera, and later he became assistant
to J. J. Pohl, professor of chemical technology in Vienna. In 1879 Eder
published Die chemischen Wirkungen des far bigen Lichtes, which was
translated into French and English. With E. Valenta, also a student
under Professor Pohl, he investigated the composition and method of
producing iron oxalate and its compounds, then little known, which
later became important in connection with platinotype and other iron-
printing processes.

During the year in which Eder substituted for Dr. Hein, professor
of chemistry at the technical high school at Troppau, he completed his
report on the mercuric-oxalate photometer, which he started to write
in Vienna. He was the first to establish the dominating sensitiveness of
the ultraviolet and the coefficient of light reaction.

Dr. Eder then returned to the technical high school in Vienna, and
in June, 1880, he was appointed associate professor of photochemistry
and scientific photography. In this office the young scientist was sup-
ported by the Vienna Photographic Society, which welcomed this
revival of photochemical research.

The introduction into England (1871-74) of silver bromide gela-
tine emulsions, of which little was then known, attracted the attention
of Eder, who directed all his energies to this promising field. In 1880
he published in the Pbotographische Korrespondenz a series of basic
experimental studies, which later appeared as a monograph under the
title Theorie und Praxis der Pbotographie mit Bromsilber gelatine; this
was also translated into French and English. In the same year appeared
his treatises on the dissociation of ammonium bromide solutions, and in
1 88 1 , on the chemical analysis of gelatine and collodion emulsions.

As early as 1879 Eder published the fact that for developing the
newly discovered gelatine dry plate the ferric-oxalate developer of-
fered definite advantages over the pyro-ammonia developer, the only
one in use up to that time. Together with G. Pizzighelli, Eder developed
a silver chloride gelatine process. Following this up, Eder alone dis-
covered the silver chloride bromide gelatine process, which he un-
selfishly offered to the public for use in photography. As a result of
these two discoveries a great industry for the manufacture of photo-
graphic art paper and of positive films for motion pictures developed
and spread throughout the world.

Meantime the Photographic Society of Vienna considered establish-
ing a photographic research institute, but the road toward the realiza-

722 JOSEF MARIA EDER

tion of this plan was long and difficult. In 1882 Dr. Eder was appointed
professor of chemistry and physics at the trade high school in Vienna.
Here he had well-equipped laboratories at his disposal, and from here
he published his well-known researches on the reaction of the silver
halide compounds to the solar spectrum and on the action of dyes and
other substances on photographic emulsions. These articles appeared
in the reports of the Academy of Sciences of Vienna. Dr. Eder’s ex-
periments establishing the superiority of iodo-eosin (erythrosin) over
eosin (bromeosin), heretofore used exclusively, were of practical
value. Following that discovery erythrosin has been used exclusively
by the manufacturers of orthochromatic plates. In 1881 Eder pub-
lished his spectral-analytical investigations on light sources for photo-
graphic use, and later he continued these researches. His treatises and
reports on researches and experiments in the field of photochemistry,
photometry, sensitometry, on photographic objectives, etc., are too
numerous to mention.

Instantaneous (snapshot) photography, which was rapidly growing
in importance, was ably dealt with by Eder in his monograph Die Mo-
ment photo graphie ( 1 st ed., 1880; 2d ed., 1883), which was also trans-
lated into French. All Eder’s works had one common purpose— prac-
tical application without regard to the pursuit of extraneous objects.

During the early period of his photographic researches Eder was
greatly handicapped by the fact that the meager literature of photo-
chemistry of that time was scattered throughout a vast body of scien-
tific and technical publications and difficult to find. No comprehensive
and scientific work on the subject similar to Gmelin’s Handbuch der
Chemie was available to the photographic student. This gave him an
incentive to create such a work. Having assembled and arranged his
data, he was able, in 1884, to complete the first volume of his widely-
known Ausfubrlicbes Handbuch der Photographie, which was subse-
quently followed by many other volumes and passed through several
editions. This standard work arises above a mere compilation of data
because of the volume of original investigation and research by Eder
included in it. Of no less importance was Eder’s Jahrbuch fur Photo-
graphie und Reproduktionstechnik. This is the most comprehensive
review we have of the development of photography from 1887 to the
present time.

In 1888 efforts were renewed to found an institute in Vienna for the
study and research of the graphic arts. This was finally accomplished

JOSEF MARIA EDER 723

through the Ministry of Education under the name “Graphische Lehr-
und Versuchsanstalt,” according to Eder’s original plans for its or-
ganization. In 1889 he was appointed director of this institution, the
history of which has been outlined in Chapter XCVI.

The studies covered the entire field of photography, in its application
to portraiture, landscape and scientific photography as well as its use
in the photomechanical processes (heliogravure, photolithography,
line etching, halftone, and both hand photogravure and rotogravure,
etc.). Adequately equipped studios and printing plants were installed.
In order to systemize an intelligent and uniform method of study for
both the teacher and the student of photography, Eder prepared his
Rezepte, T abellen und Arbeitsvorschriften fur Pbotograpbie und Re-
produktionstecbnik, first published by W. Knapp in Halle (1889);
it has since gone through many editions.

At the time of founding the institute, photography was passing
through a stage of transition from the use of a collodion to a gelatine
plate, from printing on albumin paper to collodion and gelatine silver
chloride (printing-out), silver bromide and silver chloride (develop-
ment) papers. Amateur photography made unprecedented strides and
blazed the trail also for professional photography. New types of lenses
and other appliances and devices were placed on the market. Tests for
the usefulness of these appliances were made in Eder’s laboratory and
proved of great value to the profession. Numerous improvements and
new working methods, as well as the results of extensive experiments,
were published from time to time by Eder and his associates in the
technical journals and were included in the lecture to the students of
the institute by practical demonstrations. Many exhibitions were or-
ganized along these lines. A special department of this institution, under
the personal direction of Eder for a number of years, has been devoted
to the investigation of forged legal and other documents.

Eder was very active in promoting the application of photography
to all branches of science. Physicists, chemists, astrophysicists, geode-
sists, geographers, archaeologists, zoologists, botanists, physiologists,
anthropologists, hygienists, many of them celebrities (for instance,
Ernst Mach) visited him from all parts of the world and found him
always ready with assistance and inspiration. His varied and thorough
knowledge, his keen insight, and his gift of quick perception enabled
him to give counsel and point the way out of many difficulties. In his
laboratory Lieutenant Scheimpflug perfected the methods of aerial

7 2 4 JOSEF MARIA EDER

photography used in cartography and surveying. As is well known, in
1896 Dr. Leopold Freund, of the University of Vienna, perfected the
use of X rays in therapy at Eder’s photochemical laboratory. Together
with Dr. Freund, Eder discovered in the naphtoldisulfonic salts, which
rapidly absorb the ultraviolet light, a protection against sunburn, which,
patented in 1923 under the trademark “Antilux,” became very popular.

Eder was particularly attracted to the study of sensitometry, acti-
nometry, spectral analysis, and spectrography. Then he studied the
action of the solar spectrum on photographic emulsion by means of a
glass spectrograph, and in 1889 he constructed a quartz spectrograph,
through which he was the first to establish the ultraviolet emission
spectrum of burning carbohydrates and that of the ammonium-oxygen
flame ( 1 890-92) ; he also investigated the reaction of the Bunsen burner
in ultraviolet, the absorption of various kinds of glass, the emission
spectrum of mercury light, and magnesium light, etc. In 1895 he re-
ceived from Rowland in Baltimore large diffraction gratings for spec-
trography, which he used for wave-length measurements of the spark
and arc spectra of elements. He was in constant communication with
Carl Auer Von Welsbach, who separated the supposed element into its
true elements praseodymium, and neodymium, ytterbium, and thallium.
Eder took wave-length measurements of the elements cassiopeium,
yttrium, samarium, gadolinium, europium, dysprosium, and terbium,
and so forth, which ranged from the deepest ultraviolet to red, resulting
in many conclusions reported by Professor Heinrich Kayser, of Bonn,
spectral analyst, in his Handbuch der Spectroskopie. Dr. Eder, with
Valenta, made careful wave-length measurements of the spectra of
sulphur, chlorine, and bromine in vacuum tubes under various pres-
sures. These spectral-analytical investigations by Eder were published
with excellent photogravure illustrations in the records by the Academy
of Sciences of Vienna; the wave-length measurements of the rare ele-
ments by Auer are published in the reports of the sessions of the
academy.

Most worthy of mention is the Atlas typischer Spektren, by Eder
and Valenta, published by the Academy of Sciences of Vienna ( 1 st ed.,
191 1; 3d ed., 1928). It presents the spectra of the rare elements based,
on first-hand observations and contains many valuable spectral photo-
graphs. A summary of the photographic, photochemical, and spectral-
analytical investigations made by Eder and Valenta is found in the
now-scarce voluminous work Beitrdge zur Pbotochemie und Spek-

JOSEF MARIA EDER 725

tralanalyse (Vienna and Halle, 1904, 786 pages, 93 illustrations in the
text, and 60 full-page plates).

Eder wrote the monographs Quellenschriften zu den frzihesten
Anfdngen der Photographic (1913) and Johann Heinrich Schulze
(Vienna, 1917). He urged the publication of the monographs on A.
Martin, 1921 (by Professor A. Bauer) and on Karl Kampmann. The
richly illustrated historical work Vber Schloss Miinichau bei Kitz-
biihel in T irol (1915) and the work on Kissling, Beitrdge zur Kenntnis
des Einflusses der chemischen Lichtintensitat auf die Vegetation, were
also written by him.

He collaborated in many collective scientific works, such as: “Licht,
chemische Wirkungen,” in Fehling’s Neues Handworterbuch der
Chemie (1886, Vol. IV); Meyer’s Grosses Konversations-Lexikon
(6th ed., 1902-8); Otto Lueger’s Lexikon der gesamten Technik (1st
and 3d eds.); and Max Geitel’s Der Siegeslauf der Technik (3d ed.,
1928).

Eder was also associate editor of the retrospective catalogue of the
Austrian Exhibit at the World’s Fair at Paris, in 1900, to which he
contributed the “Geschichte der Oesterreichischen Industrien.”

In addition to writing on the history of photography, he presented
collections of examples, by photographic processes, typical apparatus,
and so forth, to the Graphische Lehr- und Versuchsanstalt, to the
Technisches Museum fur Industrie und Gewerbe, Vienna, and to
the Deutsche Museum, Munich.

Eder attended numerous congresses and exhibitions. In 1887, at the
invitation of the French Academy of Sciences, he became a member
of the First International Congress on Astrophotography. He partici-
pated in the International Congresses of Applied Chemistry, which
met at Vienna, 1898, at Berlin, 1904, and at Rome, 1906. He organized
a large exhibition of scientific photography at the Vienna University,
on the occasion of the eighty-fifth annual meeting of German natural-
ists and physicians at Vienna (September, 1913). Due to his able direc-
tion, the exhibit of the Lehr- und Versuchsanstalt attracted con-
spicuous attention at the World’s Fair at Paris in 1900, at St. Louis in
1904, at the International Photographic Exhibition, Dresden, in 1909,
and at the Leipzig World’s Fair of the Book and Graphic Industry,
19151

Eder assisted the Austrian legislature in drafting a bill for the pro-
tection of the rights of inventors in the field of photography; the law

7 2 6- JOSEF MARIA EDER

went into effect in 1895 and was warmly welcomed by professional
photographers. As a result the Austrian government appointed him
court expert in the field of the graphic industry and chairman of the
government department of experts on patent rights; he served as a
member of this commission for a number of years.

On the occasion of the twenty-fifth anniversary of the establishment
of the Graphische Lehr- und Versuchsanstalt Eder was honored by
the faculty, who presented him with a silver plaque bearing his por-
trait.

The history of the Graphische Lehr- und Versuchsanstalt was pub-
lished by the institute in 1913 as a memorial. It was executed in the
institution and illustrated with 63 full-page plates. Artistically and
technically it represents the height of accomplishment and demon-
strates the excellent and varied activities engaged in by this institution
of learning under Eder’s guidance.

In addition Eder lectured for many years as professor of photo-
chemistry at the technical high school in Vienna, where in 1892 he
became assistant professor and in 1902 full professor. In 1925, having
reached the age of retirement, he withdrew from teaching, showered
with many honors. In 1930 he was awarded the honorary degree of
Doctor of Philosophy and Science at the technical high school in
Vienna. He is a member of the “Kaiserlich Leopoldinisch-Carolinischen
deutschen Akademie der Naturforscher” and of the Academy of
Sciences at Vienna; honorary president of the Photographic Society,
Vienna; honorary member of the Association of Austrian Chemists
and of many amateur and professional photographers’ associations in
Austria, Germany, England, Belgium, France, Sweden, Denmark, and
America, as well as of the former Imperial Russian T echnical Society
of St. Petersburg and the former Imperial Society of Physicians in
Vienna.

Dr. Eder received many decorations from the rulers of prewar
Europe. He was Knight of the Imperial Austrian Order of the Iron
Cross, Knight of the Leopold Order, Commander of the Austrian
Francis-Joseph Order, of the Saxon Albrecht Order with Star, officer
of the French Legion of Honor, and commander of the Swedish Wasa
Order. During the World War he was decorated by Emperor Carl
with the gold war cross for his civil services and by the Austrian
Republic with the great decoration for distinction. Of the numerous
medals of honor which Eder received, we mention only: The Elliot

JOSEF MARIA EDER 727

Cresson gold medal of the Franklin Institute in Philadelphia; the gold
medal of the Vienna Photographic Society, also their Voigtlander
medal; the gold Swedish Adelskold medal; the Plossl medal; the Petzval
medal; the Maria Theresa medal of the Vienna Camera Club; the
Daguerre gold medal of the Photographic Society in Berlin; that of
the Amateur Photographer’s Club of Vienna; the Wilhelm Exner
medal of the Lower Austrian Trade Associations in Vienna; the Sene-
felder medal of the Gremium of Lithographers and Copper Printers
of Vienna; the progress medal of the Royal Photographic Society of
Great Britain; the Peligot medal of the Societe frangaise de Photog-
raphic; and the Japanese medal of honor of the Friends of Photog-
raphy in Tokyo.

Eder’s personality has been aptly described in the following words
by one of his colleagues, Professor Dr. Alfred Hay, of Vienna (1892-
1 93 1 ), in the Phot.Korr. (April, 1930, Vol. LXVI, “Zum 75. Geburts-
tage Eder’s”:

The three most outstanding qualities in Eder’s work are: the purely sci-
entific ability to sense relationships and adjust them; the ability of the
technician to subserve scientific findings to technical aims; and finally,
the ability of the organizer to direct and guide his co-workers with a deep
psychological understanding of their individual capabilities.

Eder was able through his insight into human thought to develop both
men and their labors, and he often succeeded in difficult situations, where
others would have failed, because of his personal charm and sympathetic
approach. It may be conceded that although he fought vigorously many
an opponent, he never used unfair means.

Eder’s favorite subject has been and still is the history Of photography.
For this fascinating study he is especially well equipped by his compre-
hensive knowledge of the subject and his extraordinary memory.

Eder represents the type of scientist who has become more rare every
day. By this I mean a man of great learning, sound judgment, and— what
is more important than learning— human sympathy and tact.

This pen picture of Eder would not be complete were we to present
him merely as a scientist and scholar, omitting the man. However, to
relate his human qualities is both a pleasant and an enjoyable task.

Notwithstanding his serious conception of life’s problems, his is a
genial and joyful nature. The passing years have left no traces upon
him; he keeps a young heart and such a youthful spirit that the younger
generation may well envy him.

From nature, which he loves above everything else, Eder has

728 JOSEF MARIA EDER

gathered for years strength and inspiration, thus keeping his body and
spirit young and buoyant. It is indeed a great delight to observe our
master wandering about in the garden of his beloved estate, “Villa
Anna,” in Kitzbiihel, Tyrol, among his exotic plants, examining beetles
and butterflies, watching his meteorological and photometric instru-
ments, and with a hearty “Hello” extending a welcome to an un-
expected visitor with the old-time Viennese cordiality. All at once the
solitary student of nature in his peasant’s blouse is transformed into
the man of the world, and the visitor is carried away by the charm of
his host. This happens daily, because scientists, friends, and acquain-
tances come from all parts of the world to seek his counsel or the warm
hospitality of his cheerful household. Eder is most happy when at
Kitzbiihel. His country home, named “Villa Anna” after his wife,
is his refuge from the din and turmoil of the big city. Here he has in-
stalled a comfortable workshop, fully equipped with the necessary
paraphernalia for his studies.

Eder may well look back upon his life’s work and accomplishments
with pride and with the rare satisfaction of having earned the respect
and appreciation of the scientific world, as well as the love and admira-
tion of those who have had the privilege of knowing him intimately.

Notes

CHAPTER I

1. For a more extensive treatment of the subject see Wiedemann,
Annalen, XXXIX (1890), 470.

2. See also Ferd. Rosenberger, Geschichte der Physik in Grundziigen
mit synchronistischen Tabellen (Brunswick, 1882).

3. After Aristotle’s death his whole library, including his manuscripts,
was left to his successor, the Greek philosopher Theophrastus (390-286
b.c.). After the latter’s death the library changed hands many times by
inheritance. It is said that later, for a period of a hundred years or more,
they lay hidden in a cellar to prevent their being stolen and were event-
ually completely forgotten. About 100 b.c., Appellikon of Teos, a wealthy
bibliophile, is said to have discovered them and brought them to Athens,
where they were published. In 87 b.c., when Sulla took Athens, he had
them brought to Rome. About 70 b.c. Andronikus of Rhodes rearranged
the manuscripts and made a catalogue of them. In this order they have
remained to the present day.— Metaphysik, by Aristotle, Kirchmann ed.,
1871, 5).

4. For criticisms as to whether this work is genuine see Wilde, Ge-
schichte der Optik (1838), I, 9.

5. In 1792, in the Annals of Botany, by Usteri, St. 3, p. 237, Von Hum-
boldt called attention to this statement of Aristotle; he, however, made
Aristotle say more than the latter really did utter, since Heinrich points
out in his Von der Natur und den Eigenschaften des Lichtes (1808), p. 33,
that Goethe, in his Geschichte der F arbenlehre (Hempel ed., XXXVI,
22) gives a translation of this passage from the Greek original.

6. For further notes on earlier historic research data on the previous con-
ceptions of the development of the various colors of the skin of the human
race see Landgrebe, Fiber dasLicht (1834), p. 373; see also Ebermaier, Ver-
such einer Geschichte des Lichtes und dessen Einfluss auf den menschlichen
Korper (1799), pp. 183, 199; Latin edition of the latter, Connnentatio
de lucis in corpus humanum efficacia (1797); see also Horn, Fiber die
Wirkungen des Lichtes auf den lebenden menschlichen Korper mit
Ausnahme des Sehens (1799).

7. In this note the reference to the “silver plate” is erroneous, for the
original mentions a “gold plate.”

8. Pliny frequently does not properly discriminate between minium,
mercuric sulphide, and ocher.

730 NOTES TO PAGES 8-12

9. See Magnus, Die geschichtliche Entvoicklung des Farbensinnes
( 1877), p. 14; see also Wiegmann, Die Malerei der Alten in ihrer Anvoen-
dung und Technik (1836), p. 210.

10. Experiments were made and reported on by Chaptal ( Annales de
Chimie, 1809, Vol. LXX); Davy ( Philos . Transact., 1815); Gilbert ( Annal .
f. Physik, 1816); Geiger {Magazin fur Pharmazie, XII, 135); Junius ( Von
der Malerey der Alten, 1770); Schafhautel (Dingler’s Polytechn. Journ.
XCV, 76); Artus ( Der Technolog, 1877, I, 25). Compiled in Keim, Die
Miner almalerei (1881) and Wiegmann, Die Malerei der Alten (1836). As
source material on the colors among the ancients see Rochette, “De la
peinture sur mur chez les anciens,” in Journal des savants (1833); Roux,
Die Farben, ein Versuch iiber Technik alter und neuer Malerei (1824);
Bottiger, Ideen zur Archaologie der Malerei (181 1); Walter, Alte Maler-
kunst (1821); Fernbach, Die enkaustische Malerei (1845); Rhode, Vber
die Malerei der Alten (1787); Fiorelli, Kleine Schriften (1806); Grund,
Die Malerei der Griechen (1810). There were continuous controversies
over the technique of the paintings in Pompeii, Herculaneum, and Stabiae,
following the publication of the Pitture antiche d’Ercobano e contari
(1757) and up to the publication of Helbig’s Wandgemalde der vom
Vesuv verschiitteten Stadte Campaniens and Donner’s treatise Vber die
antiken W andmalereien in technischer Beziehung, which were settled by
the last-mentioned work, 1868.

CHAPTER II

1. Only in the twentieth century was it discovered that light had the
property of developing magnificent dyes of all kinds through photo-
oxidation of colorless leuco-base pseudo-dyestuffs.

2. Dr. Dedekind, Vienna, wrote an excellent historical essay on purple
and its sensitivity to light. This study was published in French also: Dede-
kind, La Pourpre verte [ 7 ] et sa valeur pour ^interpretation des ecrits
des anciens, Paris, 1899.

3. H. Flach, Die Kaiserin Eudoxia Makrembolitissa, eine Skizze aus
dem byzantinischen Gelehrtenleben des XI. Jahrhunderts, Tubingen, 1876.

4. Krumbacher, Geschichte der byzantinischen Literatur von Justin-
ian bis zum Ende des ostromischen Reiches {521-1453)', 2d ed. (1897),
p. 578, n. 240.

5. Cole’s letter “Observations on the Purple Fish” was published in
Phil. Trans. (XV, 1278) in 1685; also, in a French translation in Journal des
Savants (1686), p. 356.

6. Histoire de I’Academie Royale des Sciences (Paris, 171 1), p. 6.

7. In his Geschichte der Optik, to which reference will be made fre-
quently later, Priestley names Duhamel du Monceau as the first who realized

NOTES TO PAGES 12-16

73 i

“that in the light some things change color and structure.” According to
my research on the history of photochemistry this statement is not correct,
for we owe to other scientists the priority of the discovery of chemical
light effect. See statements of various authors on purple in Dedekind’s ex-
haustive monograph La Pourpre, footnote 2, supra.

8. Histoire de I’Academie Royale des Sciences (Paris, 1736), p. 49. It
is difficult to locate this treatise for references to it are both infrequent
and brief. In Ebermaier and in Heinrich’s otherwise very carefully edited
Von der N atur und den Eigenschaften des Lichtes (a prize-winning work
at Petrograd in 1808), the references (1711 and 1746) are also incorrect.
This erroneous data we wish to correct here. See also Landgrebe, Vber
das Licht ( 1 8 34), p. 47 1 , where there is a detailed description of Duhamel’s
experiments.

9. . . ce qui prouve que le Soleil agit d’une fafon tres singuliere et
tres efficace sur le sue colorant dont il s’agit.”

10. See P. Friedlander, Vber den antiken Purpur von Mur ex brandaris.
Report of the Akademie der Wissenschaften, Vienna, June 6, 1907. See
also a paper read before the Chem. Phys. Ges. on January 26, 1909, in
Ost. chemiker-Zeitung (1909).

11. Soon after the publication of the above-mentioned studies, which
aroused so much attention, Professor P. Friedlander left Vienna and ac-
cepted an appointment in Germany.

CHAPTER 111

1. According to Wiegleb, Geschichte des Wachstums der Chemie
( 1792), p. 52. Wiegleb adds: “Kircher points out that in the original manu-
script of Firmicus's works in the Vatican Library there is no mention of the
word ‘alchemy.’ It seems probable that the insertion was made deliberately
by copyists in order to favor falsely ‘alchemy.’ Mundus subterraneus , II,

2 35 -”

2. Kallid Rachaidibis, “Giildenes Buch der dreyen Worter,” published
as an appendix to Geber’s Chymischen Schriften (Vienna, 1751), p. 222.

3. Our author mentions three constellations: the first when the sun has
entered Ram and is in ascension; the second, when the sun has approached
the Lion, and the third when the sun has reached Sagittarius.

4. Printed in Schroder, Neue alchimistische Bibliothek (1774), IV, 222.

5. Ibid., p. 159.

6. Schmieder ( Geschichte d. Alchemie, 1832, p. 30), who copies the
inscription from Theatrum chemicum.

7. See Kopp, Beitrage zur Geschichte der Chemie (1869-1875), p. 381.

8. Ibid., p. 385.

9. Dierbach, Beitrage zur Kenntnis des Zustandes der Pharmazie im 16.

NOTES TO PAGES 16-22

73 2

und ty. Jahrhundert; Kastner, Repertoriumf. d.Pharmazie (1829), XXXII,
5 2 -

10. Gerber, Curieuse vollstdndige chymische Schriften (Vienna, 1751),
p. 17.

1 1 . See Schmieder elsewhere.

12. Ibid., p. 287.

13. Morhoffi, Oratio de laudibus. Aurip. 21.

14. Friedrich Geissler’s Baum des Lebens; oder Bericht vom ivahren
Auro potabili, p. 21, para. 14, and Johann Christophorus Steeb, Elixir solis
et vitae, para. 20.

15. Ibid., p. 56.

16. See Theatrum chemicum, Vol. VI; also Becher, Chymische Con-
cordanz (Leipzig ed., 1755), p. 146.

17. Ibid., p. 135. Spies adds in his Concordantzs “This shows how the
dew, the rays of the sun, the influence of the planets are also instru-
ments and means through which the heavenly energies combine with that
of the earth.”

18. Becher, Chymische Concordanz, pp. 152, 155.

19. Ibid., pp. 164, 175.

20. An element could be depicted by a series of different symbols, as
shown in the table on p. 00, but no other signs can be applied to designate
this element.

21. A. Bauer, Wiener numismatische Zeitschrift, XXIX, 323; A. Bauer,
Chemie und Alchimie in Osterreich bis zum Beginn des 19. Jahrhunderts
(Vienna, 1883, R. Lechner, pub.); A. Bauer, Die Adels do kumente Oster-
reichischer Alchimisten und die Abbildungen einiger Medaillen alchim-
istischen Ursprungs (Vienna, 1893, Holder, pub.).

22. Christian Wilhelm Baron von Kronemann, under the pretext of being
able by use of alchemy to turn quicksilver into silver and gold, deceived
his sponsor with his alleged processes— as Kohler puts it— as long as “the
Ducal silver dishes and the money advanced by the first court chaplain,
Dr. Lilien, lasted.” When his fraudulent practices were discovered, he
was imprisoned in the Red Tower of the Fortress Plassenburg. He did not,
however, stop experimenting even there, using silver he secured by force-
fully opening cupboards and stealing old silver, “gift cups.” With the
stolen silver a soldier named Hans Poltzen provided him with a red uni-
form. In this disguise he fled to Bamberg, where he was arrested on the
bishop’s order, returned by escort to the Fort in Kulmbach. There he
was hanged in his stolen red uniform.

23. Geber, De inventione veritatis sine perfectiones incerto inter prete
alchemia Geberi cum reliquies (Bemae, 1545); Gmelin, Geschichte der
Chemie (1797), I, 19; Schmieder, Geschichte der Alchemie (1832); Kopp,

NOTES TO PAGES 2

3 " 3 1 733

Geschichte der Chemie; M. Berthellot, Die Chemie im Altertum und
Mittelalter (Leipzig and Vienna, 1909). Of especial importance is Edmund
O. von Lippmann’s Entstehung und Ausbreitung der Alchemie Vol. I,
1919, Vol. II, 1931.

24. Albert the Great, under the heading “Ignis volans,” describes also
in his treatise De mineralibus mundi gun powder and its production from
sulphur, coal, and saltpeter. Incidentally, he also remarks that the studies
of his contemporary Roger Bacon also include definite traces of his know-
ledge of gun powder; see Wiegleb, Geschichte des W achstums und der
Erfndung der Chemie (1792). I, 137. See “Albertus Magnus von Koln
als Naturforscher und das Kolner Autogramm seiner Tiergeschichte”
(Osterr. chemiker-Zeitung , 1908, p. 274).

2 5. According to tradition, Basilius Valentinus differentiated with chem-
ical symbols bismuth and zinc and produced pure mercury, discovered
muriatic acid, ammonia, gold fulminate, and acetate of lead. It was he
who determined the precipitation of silver solutions by sodium chloride
and copper. The most voluminous edition of Basilius Valentinus’s col-
lected papers which was greatly improved by some old MSS added to
from the Preface of Doctor Petraeus, was published by Gottfried Richter,
Hamburg (1717 and 1740). Later research, however, indicated that the
publisher of the first edition of the legendary Basilius Valentinus was
J. Tholde, the secretary of the Rosicrucian Order, who was also a partner
in some salt mines.

26 . 1 follow, in this narrative of the writings of Basilius Valentinus, mainly
the information kindly presented to me and put directly at my disposal
by Dr. Franz Strunz, retired professor of history of natural sciences at
the Vienna Institute of Technology (1929). His information to me con-
cludes by referring me to the Buck grosser Chemiker.

27. The exact title of this work is Osualdi Crollii, Veter ani Hassi
Basilica chymica continens; philosophicam propria laborum experientia
confirmatam descriptionem et usum remediorum chymicorum selectis-
simorum e lumine gratia et naturae desumptorum (Frankfort, 1609). This
first edition is very rare, and this author found a copy in the Wiener
Hofbibliothek. B. Poggendorff, in his otherwise complete Biographisch-
literarisches Lexikon (1863 ), does not mention this oldest edition of Crollius.

28. In Basel (1570) Risner published the work Thesaurus opticae, in
which the then-known Arabic scientists and their knowledge on the sub-
ject of light are recorded (Fiedler, De lucis effectibus chemicis, 1834, p. 2).

29. See Felix Fritz, Chemiker-Zeitung ( 1914, No. 22); Phot. Rundschau
(1914, p. 221, and 1915, p. 30); Eder, Quellenschriften z u den friihesten
Anfdngen der Photographie (1913), p. 173; Eder, “Zur Geschichte der
Lichtempfindlichkeit der Silbersalze,” Photo. Industrie (1925, No. 37).

734

NOTES TO PAGES 33-39

CHAPTER IV

1. Feldhaus, Leonardo der Techniker und Erfinder (Jena, 1913), pp.
7 1 * 72 -

2. La Hyre’s work was published in 1711 (La Lumiere, 1855, p. 150).

3. In English: Natural and Original Drawings Dedicated to His Holy
Imperial Majesty Leopold I, the Undefeated and Indefatigable Champion
of the Catholic Religion.

4. The work, printed in 1748 in Nuremberg by the copper engraver
M. Seligmann, contains illustrations of plants, as imprinted by nature her-
self. The method of production is exactly described in the work by Ernst
Martius (Wetzlar, 1784) and Joh. Conr. Giitle (1793), p. 1 1 9.

CHAPTER V

1. M. von Rohr wrote in Zentralztg. f. Opt. und Mech. (1925), pp.
233 ff., an extensive historical description of the development of the
camera obscura. He describes it as a showroom, a portable aid to drawing,
a peep-box, and so forth, and presents interesting old illustrations of such
apparatus.

2. See Priestley, Gescbichte der Optik (1772); Fischer, Geschicbte der
Fhysik 1801 bis 1806; Waterhouse, The Phot. Journal (1901), XXV, 270,
also The Journal of the Camera Club (1902), XVI, 1 1 5; Eugene Muntz,
Prometheus (1899), p. 204, publications of the French Academy of Scien-
ces. The original passages from related works of Roger Bacon, Caesariano,
Porta (1558 and 1589), Barbaro, and so forth, are reprinted in Waterhouse,
“Notes on the Early History of the Camera Obscura,” The Phot. Journ.
(1901), Vol. XXV, No. 9).

3. The 33d volume of the “Kiinstler-Monographien” of H. Knackfuss
(1898), published by Velhagen & Klasing, deals with Leonardo da Vinci.
See Feldhaus, Leonardo der Techniker und Erfinder (pub. Eugen Died-
erich, Jena, 1913), p. 102. O. Werner, Zur Physik Leonardo da Vinci
(Erlangen, 1910), p. 114. Da Vinci is also looked upon as the founder of
modem anatomy; see Rudolf Disselhorst, Berichte der Kais. Leopoldin-
ischen deutschen Akademie der Naturforscher (1929), V, 51, “Das bio-
logische Lebenswerk des Leonardo da Vincis.” Otto Werner compiled an
extensive description of the publications Zur Physik Leonardo da Vinci
(Internationale Verlagsanstalt fur Kunst und Literatur, Berlin). He de-
scribes in this work at great length the famous painter’s research on the
theory of vision, also through binoculars and stereoscopes, optical mirages,
diffusion of light, camera obscura, and images through noncircular aper-
tures, catoptrics, dioptrics, acoustics, heat, magnetism. He also gives a
thorough account of the physical science of those days.

735

NOTES TO PAGES 42-49

4. Waterhouse, The Journal of the Camera Club (1902), p. 124.

5. The earliest copy (French), dated 1588, preserved in the Bibliotheque
Nationale in Paris, is a second edition of Porta’s Magia naturalis. Its title is:
Jo. Bapt. Portae, Neapolitani magiae naturalis libri xx, ab ipso autore
expurgati et super aucti, in quibus scientiarum naturalium divitiae et
delitia demonstrata Neapoli DDXXXVIII. Another edition is dated 1589
and contains Porta’s portrait with the inscription “anno aetatis quinqua-
gesimo.”

6. “Die Camera obscura bei Porta,” Mitteillungen zur Geschichte der
Medizin und der N aturwissenschaften (1919), XVIII, No. 1.

7. Priestley, Geschichte der Optik. German edition, 1776, p. 30.

CHAPTER VI

1. Sutton, Phot. Notes (Sept. 15, 1858), III; also Phot. Journ. (1862),
p. 362.

2. See Brewster, The Stereoscope (London, 1850).

CHAPTER Vll

1. Rosenberger, Geschichte der Physik, II, 120. For the genesis and the
first demonstration of the magic lantern refer to the following treatises of
F. Paul Liesegang: “Der Ursprung des Lichtbilderapparates,”Die Umschau,
(1919, No. 7), p. 107; “Die altesten Projektionsanordnungen,” Centralztg.
f. Optik u. Mech. (1918, Nos. 35-36, pp. 345, 355); “Der alteste Pro-
jektionsvortrag,” Phot. lnd. (1919, No. 4); “Die Camera obscura bei Porta,”
Mitteilungen z. Geschichte der Medizin u. d. N aturwissenschaften, (1919,
Nos. 80-81); “Schaustellungen Mittels der Camera obscura in friiheren
Zeiten,” Opt. Rundsch. (1919, Nos. 31-33); “Die Camera obscura und der
Ursprung der laterna magica,” Phot. lnd. (1919, Nos. 31-33, and 1920,
p. 197); “Die Projektionsuhr; eine Erfindung aus der Kindheitszeit der
latema magica,” Siiddeutsche Uhrmacher-Ztg. (1920, No. 9). See also:
“Vom Geisterspiegel zum Kino” (No. 927 of Ed. Liesegang’s Lichtbilder-
vortrage, Diisseldorf).

2. Priestley, History and Present State of Discoveries Relating to Vision,
Light and Colours (1772).

3. Athanasius Kircher mentions nothing in the first edition of his Ars
magna lucis et umbrae (1646) concerning the magic lantern; only the
second edition, published in 1671, contains a description and illustration
of it.

4. Reinhardt, “Uber den Erfinder des Projektionsapparates,” Pro-
metheus (1904), p. 314.

5. Evidently this is the same ingenious Dane who was quoted by De

73 6 NOTES TO PAGES 49-55

Monconys under the name “Welgenstein” and demonstrated in Rome
about 1660 the nature print.

6. In the original drawing this lens is described as CB, obviously due to
an error on the part of the wood engraver.

CHAPTER Vll REWRITTEN

1. F. Paul Liesegang, “Die camera obscura und der Ursprung der
latema magica,” Photographische Industrie (1920), p. 197.

2. F. Paul Liesegang, Vom Geister Spiegel zum Kino (Diisseldorf, 1918);
Die Umschau (1919), XXIII, 107; Prometheus, 1919, XXX, 345; Ceniral-
zeitung fur Optik und Mechanik (1922), No. 5; M. von Rohr, Z eitschrift
der Deutschen Gesellschaft fur Mechanik und Optik (1919), pp. 49, 61;
F. Paul Liesegang, Zahlen und Quellen zur Geschichte der Projektions-
kunst und Kinematographie, (Diisseldorf, 1926).

3. F. P. Liesegang, Photogr. Industrie (1919), p. 39; Deutschosterreich.
Centralzeitung fur Optik und Mechanik (1919, Nos. 1-2).

4. F. P. Liesegang, Deutsche optische W ochenschrift (1919), V, 152,
165.

5. Deutsche optische W ochenschrift (1920), VI, 337, 355; (1921),
VII, 20.

6. Photograph. Korrespondenz (1918), p. 349.

7. Reinhardt, Prometheus (1904), XV, 314.

8. F. P. Liesegang. Deutsche optische W ochenschrift (1921), VII, 180.

9. Centralzeitung fur Optik und Mechanik (1919), XL, 77, 85; (1922)
XLIII, 475.

10. Deutsche optische W ochenschrift (1923), IX, 2.

11. Siiddeutsche Uhrmacherzeitung (1920, No. 9), XXXI.

1 2. Centralzeitung fur Optik und Mechanik (1921), XLII, 99, 1 1 1 .

13. Der Bildwart (1924), II, 237.

14. Vom Geister Spiegel zum Kino (1917), p. 30.

1 5. Centralzeitung fur Optik und Mechanik (1921), XLII, 522; Deutsche
optische W ochenschrift (1924), X, 187, 207.

16. Niemann, Archiv fur die Geschichte der Naturwissenschaften und
der Technik (1914), V, 202.

17. F. P. Liesegang, Licht und Lampe (1925), p. 265.

18. Centralzeitung fur Optik und Mechanik (1928, No. 23).

19. Photographische Industrie (1923), p. 423.

20. Centralzeitung fur Optik und Mechanik (1928, No. 23).

CHAPTER VIII

1. Ray, Historia plantarum (London, 1686), I, 15. He ascribes the cause
of the plant’s loss of green color in darkness more to the absence of light

NOTES TO PAGES 55-61 737

than the action of air and heat. To quote his words: “Nobis tamen non
tam aer quam lumen luminisve actio coloris in plantarum foliis viridis
causa esse videtur . . . Ad hunc autem colorem inducendum non re-
quiritur calor.” For detailed description of these experiments see Bancroft,
Fdrbebucb (German edition, 1817), I, 86.

2. Goethe, Geschichte der Farbenlehre (ed. Hempel), XXXVI, 191.

3. Ibid., XXXVI, 284.

4. Lemery, Histoire de I’Academie Royale des Sciences (Paris, 1707),
p. 299.

5. Histoire de I’Academie Royale des Sciences (Paris, 1722), p. 129.
See also Crell, Chemische Annalen, II, 136.

CHAPTER IX

1. Placidus Heinrich, Die Phosphoreszenz der Korper; oder, Die im
Dunkeln bemerkbaren Lichtphdnomene der anorganischen Natur. ( 181 1 ),
P-9-

2. J. Fr. Gmelin, Geschichte der Chemie seit dem Wiederaufleben der
Wissenschaften bis ans Ende des 18. J ahrhunderts (Gottingen, 1798), II,
1 17.

3. Landgrebe, Wirkungen des Lichtes (1834), p. 125.

4. Ch. Ad. Balduini, Aurum superius et inferius aurae superior is et
inferioris hermeticum et phosphorus hermeticus; sive, Magnus luminaris
(Frankfurt and Leipzig, 1675); Kunckel, Labor atorium chymicum (1716).
p. 656; Ephem. med. phys. nat. curios. (Ann. IV in app.), p. 91; Wiegleb,
Geschichte des W achstums und der Erfindungen in der Chemie (1790),
Vol. I, .Part 2, p. 40. Kunckel in error cites 1677 as the date for the dis-
covery of Balduin’s phosphorus; this, however, is a slip of the pen, for
Balduin, in the quoted paper, described the preparation in 1675.

5. “. . . vitrum pro maxima sui parte opacis corporibus obtegerem
relicta exigua portione, quae liberum luci accessum permitteret. Sic non
rara nomina vel integras sententias chartae inscripsi et atramento notatas
partes scalpello acuto caute exscidi, et sic chartam hoc modo perforatam
vitro, mediante cera, affixi. Nec longa mora fuit, quum radii solares, qua
parte per apertam chartam vitrum testigeret, ilia verba, illasve sententias
sedimento cretaceo tam accurate et distincte inscriberent ut multis
curiosis, experimenti autem nesciis, ad nescio quod artificium rem hanc
referendi occasionem subinde dederim.” Owing to the difficulty of acces-
sibilty to the source of this work, I cite this important passage here fully.

6. Schulze’s treatise dated 1727 in Acta physicomedica Academiae
Caesareae Leopoldino-Carolinae naturae curiosorum exhibentia ephemer-
ides; sive, Observationes historiae et experimenta a celeberrimis Germaniae
et exterarum regionum viris habita & communicata singulari studio collect a,

738 NOTES TO PAGES 62-93

(Nuremberg, 1727), Vol. I, is quoted in full in Eder, Quellenschriften z u
den friihesten Anfdngen der Photographic bis zum XVIII. J ahrhundert; mit
5 heliographischen Portraten, 2 Lichtdrucken und diversem Buchschmuck,
179 pages. You will find there not only the original Latin text but also its
literal German translation. Considering these original sources, which are
made generally accessible, all objections must subside, since they are prob-
ably founded more on ignorance than on malice. The precise biography of
Schulze was written by Eder in his profusely illustrated book Johann
Heinrich Schulze; der Lebenslauf des Er finders des ersten photogr aphis chen
Verfahrens (Vienna, 1917; agent W. Knapp, Halle).

7. The history and Present State of Discoveries (London, 1772).

8. The first confirmation published by Eder, Photographische Kor-
respondenz (1881), p. 18.

CHAPTER XI

1. Neumann, Praelectiones chymicae (published by Zimmermann,
Berlin, 1740), p. 1612.

2. Histoire de P Academie royale des sciences (1737), p. 1 01. The passage
referring to silver solution reads: “La dissolution de l’argent fin dans l’eau
forte, qu’on a affaiblie ensuite par l’eau de pluye distillee, fait aussi une
ecriture invisible, qui tenue bien enfermee ne devient lisible qu’au bout de
trois ou quatre mois; mais elle paroit au bout d’une heure si on l’expose au
soleil, parce qu’on accelere Pevaporation de l’acide. Les caracteres faits
avec cette solution sont de couleur d’ardoise, parce que l’eau-forte est un
dissolvant toujours un peu sulphureux et que tout ce qui est sulphureux
noircit l’argent.”

3. Histoire de l' Academie royale des sciences (1737), p. 253. This quo-
tation is found in Berthollet, Elements de Part de la teinture (Paris, 1791 ) .

4. “Heraclius,” in Quellenschriften zur Kunstgeschichte, 1873, Vol. IV.

5. “Cennino Cennini,” in Quellenschriften zur Kunstgeschichte, 1871,
Vol. I.

6. Quellenschriften zur Kunstgeschichte, Vol. V.

7. Beccarius et Bonzius, “De vi quam ipsa per se lux habet, non colores
modo, sed etiam texturam rerum salvis interdum coloribus immutandi.”
De Bononensi scientiarum et artium institutio atque Academia commen-
ts™ (i 757 ). IV - 74 -

CHAPTER XII

1. Wallerius is also quoted in Macquer, Chymisches Worterbuch (Ger-
man tr. by Leonhardi, 1772), V, 46 n. Eder mentioned these works of
Wallerius in the third edition of his Geschichte der Photographic (1905),

NOTES TO PAGES 93-97 739

p. 64; Helmer Backstrom, in Nord. Fidskr. f. Fot. (1920), p. 43, also re-
ferred to them.

2. Also published in Taschenbuch fur Scheidekiinstler und Apotheker
fiir 1781, p. 46.

3. German edition of Priestley’s Geschichte und gegenwdr tiger Zustand
der Optik; tr. and annotated by Kliigel (1776). Kliigel’s numerous anno-
tations enhance the value of the German edition in comparison with the
English original.

4. Priestley, Experiments and Observations Relating to Various Branches
of Natural Philosophy . . . (London 1775), I, 33; II, 61. Further research
on the action of light on plants (especially Bonnet, 1778, Duhamel, Tessier,
1783, Senebier, 1782-91, and others) are not included in this historical essay,
for they belong to the science of plant physiology. See Landgrebe, Vber
das Licht (1834), p. 320.

5. Also quoted in Macquer, Chymisches W orterbuch (German tr. by
Leonhardi, 1782), IV, 165; Bergman, Opuscula physica et chemica (6
vols., Upsala, 1779-84).

6. Torberni Bergman, Opuscula physica et chemica (6 vols., 1779-90).
German edition: Bergman, Kleine physische und chemische Werke; pub-
lished after the author's death by Hebenstreit from the Latin by Tabor
(F/ankfurt on the Main, 1782-88).

7. The title of the Latin edition reads: Scheele, Aeris atque ignis examen
chemicum (Upsala et Leipzig, 1777), p. 62. The title of the German edition
reads: Chemische Abhandlung von der Luft und dem Feuer von Carl
Wilhelm Scheele Apotheker zu Koping in Schweden, der Konigl. Aka-
demie der Wissenschaften zu Stockholm, Akademie zu Turin, der Chur-
fiirstlichen Maynzischen Akademie niitzlicher Wissenschaften zu Erfurth
und der Gesellschaft naturforschender Freunde . . . (Mitglied. Upsala
und Leipzig, 1777; 2d ed., 1782). The German edition of Scheele’s S'dmt-
liche Werke ed. by Hermbstadt (Berlin, 1793), pp. 13 iff. J. M. Eder
printed a verbatim copy in its proper place for the “History of Photo-
graphy,” in Quellenschriften zu den friihesten Anfangen der Photographie
(Halle on the Saale, 1913). See C. W. Scheele ett minnesblad pa hundrade
ardsdogen of bans dod, by Cleve, with portrait and facsimile; also Scheele,
Nachgelassene Brief e und Aufzeichnungen, published by Nordenskiold;
with portrait and facsimile (1892).

8. Landgrebe, in his famous book Ober das Licht (1834), p. 3;Becquerel,
LaLumiere (1868), II, 45; Hardwich, Manual der photo gr. Chemie (1863),
p. 6; Muspratt, Enzyklopadisches Handbuch der technischen Chemie,
arranged by Kerl and Stohmann (1878), V, io77ff.

9. The priority of this discovery is not infrequently ascribed to Priest-
ley. However, it seems that Scheele and Priestley at the same time and

740 NOTES TO PAGES 97 - 101

independent of each other experimented with this property of nitric
acid. Hunt erroneously dates this discovery in his Manual of Photography
(1834, p. 335) as the year 1786 which error was reprinted in Abridgments
of Specifications Relating to Photography, issued by Great Britain, Patent
office (1861), Vol. V.

10. This means that red vapors of nitrogen tetroxide (nitric dioxide)
developed.

11. Scheele, S'amtliche Werke, German edition by Hermbstadt, p. 132,
par. 61.

12. Ibid., p. 14 1, par. 66.

CHAPTER Xlll

1. Priestley, Experiments and Observations on Different Kinds of Air
(London, 1775-77). Vol. Ill, sec. 23; Experiments and Observations Relat-
ing to Various Branches of Natural Philosophy (London, 1789). Vols. I
and III, sec. 22; Philosoph. Transact. (1799) II, 139; Gren, Journal der
Physik, II, 94, 350; abstract from Vber die Natur des Lichtes (1808), p. 36,
and Heinrich, Von der Natur des Lichtes (1808), p. 79.

2. Opoix, Observations physico-chymiques surles couleurs (Paris, 1777);
German edition: Physikalischchemische Beobachtungen iiber die Earben
(Vienna, Leipzig, 1785), p. 65. There it states: “colored bodies discolor
little by little in the air and after a certain time sustain complete loss of
their color. However, it is easily demonstrated that it is not the air which
produces the change in colored bodies, for colors remain perfect in a dark,
well-aired place ... it is not the air, but the light which destroys color.”

3. Neue Beitrdge zur Natur und Arzneiwissenschaft (Berlin, 1782), p.
200. This quotation is taken from Ebermayer, Versuch einer Geschichte
des Lichtes, (1799), and Fischer, Geschichte der Physik, Vol. VII.

4. He states: “Organization, sensation, arbitrary motion, life, exist only
on the surface of the earth and in places where light penetrates. One might
say that the myth of the fire of Prometheus is the expression of a philo-
sophical truth which, indeed, did not originate with the ancients. Nature
in the absence of light was without life, dead, without soul. A good God
created light, and through it he dispersed on the surface of the earth order,
sensation, and thought.”

5. Lavoisier, System der antiphlogistischen Theorie, German tr. by
Hermbstadt, 1792, I, 228; originally published in French, 1789.

6. Taschenbuch fiir Scheidekiinstler und Apotheker auf das Jahr 1784,
p. 160.

7. Selles, Neue Beitrage zur Natur und Arzneiwissenschaft (1782);
Gmelin, Geschichte der Chemie (1799), III, 790; Taschenbuch fiir Scheids-
kiinstler auf 1784, p. 160.

NOTES TO PAGES ioi - no

74i

8. Crell, Chemische Annalen (1784), p. 341; T aschenbuch fur Scheide-
kiinstler und Apotheker auf das Jahr 1786, p. 46.

9. Crell, Neueste Entdeckungen in der Chemie (1782), V, 70.

10. Senebier, Memoir es physico-chimiques sur I'influence de la lumiere
solaire pour modifier les etres des trois regnes de la nature (Geneva, 1782 ) ;
German edition, Leipzig, 1785. Excerpt by Crell in Neueste Entdeckungen
in der Chemie (1783), XI, 211.

11. Senebier (German edition) Physikalisch-chemische Abhandlungen
iiber den Einfluss des Sonnenlichtes, II, 212.

12. Aromatic gum from hymenoca Courbail (letter from Eder to
Translator, Dec. 5, 1932).

13. Senebier, Physikalisch-chemische, III, 12, 82, 92, 104, 108.

14. Ibid., p. 94.

CHAPTER XIV

1. “Giovanni Antonio Scopoli, born near Trentino, doctor of medicine,
at first physician in the mercury mine at Idria (Austria), then mining
councillor and professor of mineralogy at the Academy of Mines in
Schimnitz (Hungary), 1777, professor of chemistry and mathematical
sciences at Pavia, died 1788” (letter from Eder to Translator).

2. Crell, Die neuesten Entdeckungen in der Chemie (1783), VIII, 1.

3. Berthollet, Histoire de I’Academie royale des sciences (Paris, 1785),
p. 290. Lichtenberg’s Magazin, IV, 2, 40.

4. Scheele, “Observation sur l’air qui se degage de l’acide nitreux expose
au soleil,” Journal de physique, XXIX, 231; Crell, Chemische Annalen
(1786), IV, 332.

5. Berthollet, Journal de physique (1786), XXIX; Lichtenberg’s Mag-
azin, IV, 2, 40.

6. Berthollet, Essai de statique (1803); excerpt from Landgrebe, Ober
dasLicht (1834), p. 7.

7. Bindheim, Chemische Annalen (1787); see also Taschenbuch fur
Scheidekiinstler und Apotheker auf das Jahr 1788, p. 23. This passage refers
only indirectly to photography. I refer to it here because there is a con-
nection with the spoiling of the silver baths by bad filter paper.

8. Robison, in Buchner’s and Kastner’s Repertorium fiir die Pharmazie
(1822), XIII, 44, from Black’s Lectures, I, 412. Robison further states: “It
might be useful to compare the blackening property of the sun rays after
passing through nitric acid with that of the rays having passed through the
same quantity of water. The rays have a stronger effect upon the nitric acid
than on water.” Robison’s experiments were not published until about
forty years after he made them. John Robison: “On the Motions of Light,
as Affected by Refracting and Reflecting Substances, Which Are Also in

742 NOTES TO PAGES 110-114

Motion,” Trans. Soc. of Edinburgh, II, 83; Reuss, Repert. Commenta-
tionum, IV, 255. [[Letter from Eder to Translator.]

9. “Jean Antoine Claude Chaptal (1765-1832), chemist and statesman,
was director of a saltpeter factory at Grenoble, simplified the manufacture
of niter; later professor at Montpellier. He improved the manufacture of
nitric acid, alumina, and soda and introduced production of Turkish
red in France. He was secretary of the interior (1800-1804) and was made
Count de Chanteloup by Napoleon in 1811; after the restoration of the
Bourbons he retired to private life, but was elected to the Chamber of
Peers in 1819. [[Letter from Eder to Translator.]

10. Chaptal, “Observations sur l’influence de Fair et de la lumiere dans
la vegetation des sels,” Journal de physique (1788). XXXIII, 297; Lich-
tenberg's Magazin, VII, 153.

1 1 . Dize, “Sur la cristallisation des sels par 1 ’action d e la lumiere,” Journal
de physique (1789), XXXIV, 105; Voigt's Magazin, VII, 61.

12. Priestley, Philosophical Transactions (1879), p. 134; Gren, Journal
der Physik (1790), II, 94, 350.

13. Dorthes, Annales de chimie (1790), II, 92; Gren, Journal der Physik
(1790), I, 497. Crell, Chem. Annal. (1790), I, 546. He also observed that
a frog kept in darkness takes on a green of a deeper hue.

14. Saussure, “Effets chimiques de la lumiere sur une haute montagne,
compares avec ceux qu’on observe dans les plaines,” Memoires de I'Acad-
emie de Turin (1790), IV, 44; Crell, Chemische Annalen (1796), I, 356.

15. Eder, Photogr. Korrespondenz (1881), p. 128. Later C. Chistoni
wrote a historical essay on Saussure and actinometry (Bei blatter z. d.
Annal. d. Physik., 1903, p. 386).

16. Senebier, Annal. de Chim., II, 89; Crell, Chemische Annalen (1796),
I, 71.

17. German translation by Gottling under the title Handbuch der
Farbekunst (Jena, 1792). Second French edition 1804 and its German
translation (by Gehlen), Berlin, 1806.

1 8. Berthollet’s discovery of bleaching by chlorine was of the greatest
consequence in the development of bleaching industry. I mention here
an unimportant detail, which has only a slight bearing on photography;
the bleaching of old corroded copper engravings, and so forth, which
were to be reproduced photographically. Gottling, in 1791, and Madame
Masson, in 1795, discovered this (Scherer, Allgemeines Journ. d. Chemie,
1799, II, 2, 500; Handbuch fur F abrikanten, Kimstler, Handover ker . . .
oder, Das Neueste und Niitzlichste der Chemie . . . , 1799,11, 12). Under
the heading “Anwendung der dephlogistinierten Salzsaure zum Bleichen
der Kupferstiche, alten Bucher . . .” the procedure is described in detail.
The illustration was immersed in chlorinated water. After 'A -'A hour it

NOTES TO PAGES 115-116 743

was carefully taken out, passed through clean water, and dried between
blotting paper and placed between boards. This procedure was later redis-
covered time and again.

19. Hahnemann’s exact prescription is published in Crell, Chemische
Annalen (1790), p. 22.

20. Fourcroy, “Sur les differents etats du sulfate de mercure, sur la
precipitation de ce sel par l’ammoniaque . . .” Annales de chimie (1791),
X, 293, 312.

21. The relevant passage by Fourcroy reads: “Lorsqu’on verse de
l’ammoniaque dans une dissolution de sulfate (oxyduls) de mercure neutre
et bien pur, on obtient un precipite gris tres-abondant, qui, expose sur son
filtre aux rayons du soleil, se reduit en partie en mercure coulant; une
autre portion de ce precipite reste en poudre grise foncee, sans se reduire:
cette derniere se redissout completement dans l’ammoniaque . . . . Ce
depot compose . . . n’a lieu ou ne se presente dans cet etat et ainsi
melange, que lorsqu’on ne met que peu d’ammoniaque dans la dissolution
de sulfate mercuriel bien neutre. Si au contraire on met beaucoup de cet
alcali, on a un precipite . . . beaucoup plus noir et qui se reduit complet-
tement par le contact de la lumiere et sur-tout lorsqu’on l’expose aux
rayons du soleil.”

22. Vasalli, Memoires de I'Academie royale des sciences de Turin (1790-
91), p. 1 86. Crell, Chemische Annalen (1795), II, 80; Trommsdorff, Journal
der Pharmazie (1796), III, 337.

23. Vasalli states: “That much is evident; light in the process of com-
bustion colors the chloride of silver equally as sun light, differing only in
the longer time consumed by the former and producing a lack of density
in color by the later . .

24 Vasalli, Memoires de I'Academie royale de Turin (1793), p. 287;
Crell, Chemische Annalen (1795). II, 142.

25. Trommsdorff, Journal der Pharmazie (1793), I, 174.

26. Buonvicino, Memoires de I'Academie royale de Turin (1793), p. 297.
It is possible that Buonvicino confused it with Fourcroy’s light-sensitive
mercurous-oxide salt.

27. Humboldt, Versuche iiber die Zerlegung des Luftkreises (1799),
p. 234.

28. Gottling, Beitrag zur antiphlogistischen Theorie (1794), p. 51; see
also Heinrich, Vber das Licht (1808), p. 89.

29. Gren, Neues Journal der Physik (1795), II, 492.

30. Bockmann, Versuche iiber den Phosphor . . . (1800), p. 264.

31. Lentin, Gottingen, 1798, translated Mme Fulhame’s paper into Ger-
man. This is condensed in Scherer’s Allgemeines Journal der Chemie
(1798). I, 420. See Heinrich, Von der Natur und den Eigenschaften des

744 NOTES TO PAGES 117-128

Lichtes (1808), p. 106. An article: “Neue Versuche mit der Reduktion
der Metalle in Beziehung auf Farbekunst,” in Handbuch fiir Fabrikanten,
Kiinstler, Handwerker . . . (1800), III, 54, without reference to author
or source, mentions the same experiments as those performed by Mme
Fulhame and Rumford, namely, the reaction of gold and silver solutions
under action of light or hydrogen gas.

32. Fischer, Geschichte der Physik (1806), VII, 12.

33. Juch, Versuch iiber die Wiederherstellung des Goldes; Scherer,
Journal der Chemie (1799), III, 399; Landgrebe, Fiber das Licht (1834),
p. 16.

CHAPTER XV

1. Vauquelin, “Du plombe rouge de Siberie, et experience sur le nou-
veau metal qu’il contient.”

2. Vauquelin, in Scherer’s Journal der Chemie (1798), II, 2, 717; and
TrommsdorfFs Journal der Pharmazie (1800), VII, 95.

3. Fabroni, Di unatinta stabile che qui suo entrarci dalPaloc socco-
torima (Florence, 1906).

4. Scherer, Journal der Chemie (1798), II, 2, 544. Also condensed with-
out giving source in Handbuch fiir Fabrikanten, Kiinstler . . . oder, Das
Neueste und Niitzlichste der Chemie, Fabrikwissenschaft . . . (1799),
II, 109.

5. Euler, Letters on Various Subjects; new translations with annotations
and additions by Kries (1792), I, 204 42d letter.

6. Davy, “An Essay on Heat, Light and the Combinations of Light,”
Nichols. Jour. (1799), IV, 395; Gilbert, Annalen (1802), XII, 574.

7. Gilbert, Annalen, XII, 574, 581.

8. Abildgaard, “fiber die Wirkung des Lichtes auf das rote Quecksil-
beroxyd,” Annalen (1800), IV, 469; Annales de chimie, XXXII, 193.

9. Bockmann, Versuche iiber das Verhalten des Phosphors in ver-
schiedenen Gasarten (Erlangen, 1800); Scherer, Journal der Chemie, V,
243.

10. Voigt, Magazin fiir den neuesten Zustand der Naturkunde (1800),
IV, 1 2 1 ; see also Landgrebe, Fiber das Licht, p. 7 1 .

11. Trommsdorff, Journal der Pharmacie (1800), VIII, 163.

12. See also Scherer, Allgemeines Journal der Chemie (1802), VIII, 14.

13. Ibid. (1800), IV, 2, 549.

14. Subtitle: “Das Neueste und Niitzlichste aus der Chemie, Fabrik-
wissenschaft, Apothekerkunst . . .” Ill, 9.

15. Ritter, Versuche iiber das Sonnenlicht; Gilbert, Annalen (1801),
VII, 527 (short note); 1802, XII, 409. Dealt with exhaustively in Land-
grebe, Fiber das Licht, p. 28.

NOTES TO PAGES 129- 140 745

16. Trommsdorff, Journal der Pharmacie (1801), IX, 164, from Journ.
de la Soc. de pharm. de Paris, III, 433.

17. London Medical Review and Magazine, V, 1801; see also Nicholson,
Journal of Natural Philosophy, Chemistry and the Arts (1802), V, 545.

18. This is explicitly mentioned here because Hunt insisted that the
priority is entirely due to Harup; he also errs in calling Boullay (1803)
the first who discovered the light sensibility of calomel.

19. I follow here Fiedler’s statement De lucis effectibus chemicis (1785),
p. 6, without having checked it with the quoted original byWeiss, since
this work was not accessible.

20. Desmortiers, Recherches sur la decoloration spontanee du bleu de
Prusse (Paris, 1801); Gilbert, Annalen, X, 363; Scherer, Journal der
Chemie, X, 1 14.

21. Desmortiers ascribed also the secondary blue result to the action
of light.

22. Das Neueste und Niitzlichste der Chemie, Fabrikwissenschaft,
Apothekerkunst . . . (1801), IV, 135. The original article is unknown
to me. The cited journal, which was very poorly edited, was especially
lacking in its quotation of sources.

23. Gilbert, Annalen der Physik (1811), XXIX, 291.

24. Rumford, “An Inquiry into the Chemical Properties That Have
Been Attributed to Light,” in his Philosophical Papers, (1802), I, 341-65
(letter from Eder to translator).

25. Nicholson, A Journal of Natural Philosophy, Chemistry and the
Arts (1802), V, 245.

26. Charles R. Gibson, Die Photographie in Wissenschaft und Praxis
(German translation, A. Hay, Leipzig-Vienna, 1929), p. 10.

27. Notwithstanding the fact that the English original on the method
of Wedgwood and Davy was published in 1802, almost all German trans-
lations give 1803 as the publication date. See Meteyon, Wedgwood and
His Works (1874); E. Mehegard, Memorials of Wedgwood (1870);
Smiler, Josiah Wedgwood (1894).

28. For Davy’s biography see Thorpe, Humphry Davy, Poet and Philo-
sopher (Cassel & Co., Lim., London, 1901), and A. Bauer, Humphry Davy
(1778-1829), Lecture in Ver. zur Verbr. naturw. Kenntnisse (Vienna,
1904) Vol. XLIV, No. 5.

29. R. B. Litchfield wrote a book about Tom Wedgwood, in which he
hailed him as the first photographer— Tom Wedgwood, the First Photo-
grapher (London, 1903). Litchfield, in discussing Eder’s fundamental
description of Schulze’s experiments, p. 103, is of the opinion that those
experiments were so imperfect in the results at that time that they could
not be referred to as photography. Litchfield endeavors to ascribe to

746 NOTES TO PAGES 143 -147

Wedgwood and Davy the merit of discovering photography. The author,
in the third edition of his Geschichte, p. 104, remarks that it is true that
Schulze had no knowledge of fixation. Neither had Wedgwood and Davy;
nevertheless, they had always been called by various authors the first
discoverers of photography (without fixation). Due to my historic re-
search Wedgwood and Davy must cede to Schulze this priority, and to
him must be given the credit for having made the first photograph. The
priority of the discovery of the above-mentioned photographic light
images on silvered paper, of silhouettes, and of solar-microscope pictures
belongs without doubt to Wedgwood and Davy.

CHAPTER XVI

1. Scherer, Allgemeines Journal der Chemie, X, 115; Tilloch’s Philo-
soph. Magaz., XIII (No. 49), 42.

2. Gehlen, Journal, II, 91.

3. Berthollet’s statement that a current of air blackened silver chloride
is, according to Ritter, due to a mere coincidence, for a draught was
caused by a bellows having been used before which discharged coal dust
(Fischer, Vber die Wirkung des Lichtes auf Hornsilber, 1814, p. 26).

4. Thomas Young (1773-1829) was a practicing physician in London
and an eminent scientist. From 1801 to 1804 Young was professor of nat-
ural sciences at the Royal Institution. In his work Syllabus ; a Course of
Lectures on Natural and Experimental Philosophy with Mathematical
Demonstrations of the Most Important Theorems in Mechanics and Op-
tics (1802), he gave for the first time an explanation of the most import-
ant phenomena of vision and of the interference of light, based on the
wave theory. He concluded that the color sensitivity in the human eye
can be traced to the three primary colors, red, green, and violet, which
are perceived by the retina on three corresponding sensitive kinds of
fibers. This theory was elaborated by the German physicist Hermann von
Helmholtz (1821-94) * nt0 th e so-called “Young-Helmholtz Theory of
Color Sensitivity.” [This footnote was added to this edition by Dr. Eder.J

5. Poggendorff, Geschichte der Physik (1879), p. 646.

6 . Philo soph. Transactions of the Roy. Soc. of London, 1804. German:
Gilbert, Annalen ( 1 8 1 1 ), XXXIX, 262, 282.

7. For instance, Fischer, in Breslau (Kastner, Archiv f. gesamte Natur-
kunde, 1886, IX, 345).

8. Eder wrote this in the first ed. of his history (1881).

9. Nicholson, Journal, II, 117; Gilbert, Annalen, XVI, 245.

10. Gehlen, “tlber die Farbenveranderung der in Ather aufgelosten
salzsauren Metallsalze durch das Sonnenlicht,” Neues allgemeines Jour-
nal der Chemie, III, 566.

NOTES TO PAGES 149 -155 747

1 1. Disputatio chemica-phisica inauguralis, de atmosphaera, ejusque in
colores actione (1805); translated in Trommsdorf, Journal der Pharma-
cie (1809), XVIII, 221.

12. Pfaff, in Gehlen, Journal der Chemie (1805), V, 500.

13. Ritter, loc. cit., 1806, VI, 157.

14. Gehlen, Journal fur Chemie und Physik (1808), VI, 659; Land-
grebe, Vber das Licht (1834), p. 33.

15. From this remark of Ritter’s it seems obvious that he had no knowl-
edge of Saussure’s experiments with his chemical photometer.

1 6. Ritter mentions here Gilbert’s experiment in which in a vacuum sil-
ver chloride kept all of its white. This statement by Gilbert is incorrect.
Senebier had long ago discovered this property of chloride silver to
change color even in a vacuum.

17. “Dissertation chemico-pharmaceotique sur la graisse, et sur quel-
ques medicaments qui en derivent”; read before the Societe de pharmacie
de Paris 1806, Trommsdorff, Journal der Pharmacie (1807), XVI, 1, 173.

CHAPTER XVII

1. Later he moved to Bayreuth and Nuremberg. From 1818 he was a
member of the Berliner Akademie der Wissenschaften; then he resided in
Berlin, where he died in 1831.

2. “Zur Farbenlehre,” in Goethe’s Werke, Tubingen, Cotta’sche Buch-
handlung, 1810 (ed. Hempel, Berlin, XXXVI, 431).

3. Silver chloride.

4. Seebeck, “Uber die ungleiche Erregung der Warme im prismati-
schen Sonnenbilde” (presented before the academy in Berlin in March,
1819; Journal fin Chemie und Physik, by Schweigger (1824), XL, 146).
Hessler carried out in 1835 more thoroughgoing experiments on the in-
fluence of the properties of the prism on the spectrum. He studied the ac-
tion of the solar spectrum obtained through various liquid and glass
prisms on paper coated with a rubberized water solution and sprinkled
with silver chloride. Certain differences appeared in the extent of the
blackening as well as in the location of the maximum darkness and the
time in which it occurred. With water and alcohol it was approximately
o; with flintglass, 2.3 min.; with crownglass, 1.5 min.; with turpentine and
cassia oil, 12-13 minutes. In the spectrum of water the maximum of the
darkening lay in the middle of the violet close to the blue, while in the
spectrum of the “water” [mV] in the center of the violet, while in the
cassia oil it was found 23 lines outside of the violet range ( Annal. d. Phys.
u. Chem., Poggendorff, 1835, XXXV, 578).

5. When in 1830 Schopenhauer was about to publish the Latin edition
of his Farbenlehre, he consulted Dr. Seebeck of the academy in Berlin,

748 NOTES TO PAGES 155-160

who at that time was considered Germany’s greatest physicist. Schopen-
hauer asked his opinion on the dispute between Goethe and Newton. See-
heck “was extremely cautious; he made me promise that I would publish
no part of our conversation; and finally, after strong pressure from me,
he confessed that Goethe was quite right, in fact, and Newton wrong—
which, however, was not his business to publish to the world.” On this
Schopenhauer comments: “He has since died, that old coward . . . Truth
in this vicious world occupies a hard position and progresses with dif-
ficulty ...” (Schopenhauer, Vber das Sehen und die Farben, Frauen-
stadt’s Preface to the 3d ed., 1870, p. xv).

6. Schweigger, Journal, 1811, II, 262.

7. Ibid., 1812, V, 233.

8. See also Schweigger, Journal fiir Chemie und Physik (No. 219), V,
2 33 -

9. “Oil-forming gas and gases which develop from alcohol when it is
disintegrating in glowing tubes or from vegetable or animal substances in
dry distillation.”

10. Gilbert, Annalen (1811), XXXIX, 291.

11. Ruhland, in Schweigger, Journal fiir Chemie und Physik (1811),
I, 470.

12. Young, in Gilbert, Annalen (1811), XXXIX, 156.

13. Fresnel, see Poggendorff, Geschichte der Physik (1879), p. 646.

14. David, in Schweigger, Journal fiir Chemie und Physik (1813), IX,

15. A. Vogel, op. cit. (1812), p. 404.

16. Ibid., VII, 95.

17. A. Vogel, in Annales de chimie (1813), LXXXIV, 225; Tromms-
dorff, Journal der Pharmacie, XXII, 2, 209; Schweigger, Journal fiir Che-
mie und Physik (1813), VII, 95. See also Brugnatelli (Schweigger, Journ.,
1813, VII, 98).

;8. Ruhland, in Schweigger, Journal fiir Chemie und Physik (1813),
IX, 229.

19. Ibid. (1813), VII, 21.

20. See also Gilbert, Annalen (1814), XVIII, 375.

2 1. Dr. A. Vogel may well be called the precursor of the modem
photographic bleaching process, owing to his knowledge of bleaching of
organic pigments under exposure to light with complementary colors and
their consistency behind glass (see later chapters).

22. N. W. Fischer’s treatise was read before the medical section of the
Silesian Gesellschaft fiir vaterlandische Kultur, on April 25, 1812.
Schweigger, Journal fiir Chemie und Physik (1813), IX, 403. Nicolas
Wolfgang Fischer (b. 1782, in Gross-Meseritz, Moravia; d. 1850, in Bres-

NOTES TO PAGES 160-168

749

lau) practiced medicine in Breslau, first as assistant, later as full professor
at the university in Breslau, where he lectured on chemistry.

2 3. Consequently, he calls melted silver chloride “Homsilber,” the pre-
cipitated “silver hydrochloride.”

24. The German chemists disagreed in the definition of chlorine and
iodine. Some called it “die Chlorine,” “die Jodine,” others, “das Chlorin
oder Jodin” or “das Chlor oder Jod.” They soon abandoned the feminine
gender, particularly after the vigorous protest which Buchner directed
against the anomaly created by the idioms and analogies in German and
in foreign languages (Buchner, Repertor. Pharm., 1823, XIV, 456). Later
the terms “das Chlor und Jod” became general.

25. Davy, in Schweigger, Journal fiir Chemie und Physik (1814), XI,
68; from Thomsen, Annals of Philos. (1814); Phil. Trans. (1814), CIV,
74 -

26. Schweigger, Journal fiir Chemie und Physik (1814), XI, 133.

27. Journal de Pharmacie (1815), p. 49. See also Trommsdorff, Jour-
nal der Pharmacie, XXV, 1, 195.

28. Brandenburg, in Schweigger, Journal fiir Chemie und Physik
(1815), XIV, 348.

29. Schweigger, op. cit., p. 377.

30. Evidently containing sulfate of manganic oxide with “oxydul.”

31. Fromberg, in Schweigger, Journal, 1824, XLI, 269.

32. Pelletier and Cavetou, in Journal de Pharm. (1817), Vol. XI; Buch-
ner, Repertorium fiir die Pharmacie (1818), IV, 394; Annales de chimie
el de physique (1818), Vol. IX.

33. Buchner, Repertorium fiir die Pharmacie (1818I, IV, 396.

34. Annales de chimie et de physique (1818), VIII, 201; Schweigger,
Journal fiir Chemie und Physik (1818), XXIV, 309.

35. For biography and the works of Grotthuss see monographs by R.
Luther and also Oettingen, “Abhandlungen iiber Elektrizitat und Licht
von Theodor Grotthuss,” Leipzig, 1906 (No. 152 of Ostwald’s Klassiker
der Naturwissenschaften).

36. Schweigger, Journal fiir Chemie und Physik (1818), XX, 240.

37. Extract from Gilbert, Annal. Phys. (1819), LXI, 50.

38. See Grotthuss, Physisch-chemische Forschungen (Nuremberg,
1820).

39. This reaction was later recognized as due only to the escape of
iodine under heat. Therefore, the example is irrelevant.

40. See Traube, Grundriss der physikalischen Chemie (1904).

41. See Fr. Limmer, in Phot. Korresp. (1911), No. 608, on the history
of the bleaching process, particularly on the contributions of Worel and
Neuhauss.

750

NOTES TO PAGES 169-176

42. J. M. Eder, Phot. Indust. (1930), p. 1392.

43. Annals of Philos. (January, 1821); Schweigger, Journal fur Chemie
und Physik (1821), XXXI, 490.

44. Schweigger, Journal fur Chemie und Physik (1821), XXXIII, 231.

45. Annals of Philos. (September, 1821); Schweigger, Journal fur Che-
mie und Physik , XXXIII, 233.

46. Buchner and Kastner, Repertorium fur die Pharmacie (1822)
XIII, 44.

47. Buchner, Repertorium fur die Pharmacie (1823), XIV, 467.

48. Water, resp. carbonic acid, must have been polluted by organic
substances.

49. Schweigger, Journal fur Chemie und Physik (1823), XXXVIII,
298.

50. Kastner, Archiv fur die gesamte Naturlehre (1824), I, 257.

51. Chemical News (1909), XCXI, 205.

52. See Balard’s portrait in Pector, Notice historique, Gauthier-Vil-
lars, Paris, 1905. See also Chemiker-Zeitung, 1909; Repert., p. 261, by
F. D. Chataway.

53. Kastner, Archiv fur die gesamte Naturlehre (1826), IX, 345.

54. Journal de Pharmacie (April, 1826), p. 209; Trommsdorff, Neues
Journal der Pharmacie (1826), XIII, 216. It must not be forgotten that a
great role has been played by the stronger reducing action of alkaline
tannic elements (when alkaline development was introduced) in photo-
graphy.

55. Trommsdorff, Neues Journal der Pharmacie (1826), XII, 100.

56. Wetzlar, in Journal fur Chemie und Physik, by Schweigger-Seidel
(1828), XXV, 467.

57. Wetzlar, in Schweigger’s Journal fur Chemie und Physik (1827),
pp. 51, 371.

58. Mitscherlich, in Poggendorff’s Annalen (1827), IX, 413; Berzelius,
Jahresbericht ilber die Fortschritte der physischen Wissenschaften, VIII,
183.

59. Hess, in Poggendorff’s Annalen (1828), XII, 261.

60. Henry and Peisson, Journ. de Pharmac. (1829), p. 390.

61. Rose, in Poggendorff’s Annalen (1830), XIX, 153.

62. Stromeyer, in Schweigger’s Journal (1830), LVIII, 128.

63. Serullas, Annales de chimie et de physique (1831), XL VI, 392.

64. Berzelius, in Poggendorff’s Annalen (1835), XXXVI, 27.

65. Pelouze, Gay-Lussac, Annal. de chimie et de physique (1833),
LII, 410.

66. Lowig, in Poggendorff’s Annalen (1828), XIV, 485.

NOTES TO PAGES 177-189 751

67. Carbonell, Journal de Pharmacie (1833); Buchner’s Repertorium
fur die Pharmacie (1834), XL VII, 71.

68. Garot mentioned earlier ( Journ . de Pharmacie, 1826, p. 454) the
light sensitivity of mercury oxide acetate.

69. Carbonell, Archiv d. Pharmacie (1836), LV, 246.

70. Burkhardt, “Cber Verbindungen der Quecksilberoxyde mit organ-
ischen Sauren,” Brandes, Archiv d. Pharmacie (1837), II, 250.

71. Doebereiner, in Schweigger’s Journal fur Chemie und Physik
(1828), LIV, 414, 416.

72. Doebereiner, in Schweigger’s Journal (1831), LXII, 86.

73. Suckow (Vber die chemischen Wirkungen des Lichtes, 1832, p. 27)
performed experiments on the decomposition of ferric oxalate in colored
light. He found that decomposition takes place most quickly in white and
violet light, less rapidly in blue, and slowest in green light. Yellow and
orange-red light produced no change.

74. Braconot, in Schweigger’s Journal (1831), LXII, 455; Annal. de
chimie et de physique, XLVI, 206.

75. Liebig, Annalen der Pharmacie, V, 290; Erdmann, Journal fur tech-
nische und okonomische Chemie (1883), XVIII, 348.

76. Torosiewicz, in Buchner, Repertorium fur die Pharmacie (1836),
LVII, 335.

CHAPTER XV III

1. Schiibler, Annal. de chimie et de physique, XXVIII, 440; Kastner,
Archiv fur die gesamte Naturlehre (1825), VI, 33.

2. S. Landgrebe, Vber das Licht, p. 276.

3. Journal de Pharmacie (May, 1826), p. 276; Buchner, Repertorium
fiir die Pharmacie (1826), XXIV, 284

4. Serullas, first in Annal. de chimie et de physique (1827 ), XXXV, 291,
then more extensively, op. cit. (1828), XXXVIII, 371.

5. Sprengel, in Erdmann, Journal fiir technische und okonomische
Chemie (1828), III, 413.

6. The chapter referring to “Vom Licht” is also in Erdmann, Journal
fiir technische und okonomische Chemie (1830), p. 172.

7. Lampadius, in Erdmann, Journal fiir technische und okonomische
Chemie (1830), VIII, 322.

8. Robiquet, in Journ. d. Pharmacie (March, 1831); Erdmann, Journal
fiir technische und okonomische Chemie (1831), X, 417.

9. Zier, in Erdmann, Journal fiir technische und okonomische Chemie
(1832), XIV, 33.

10. Lampadius, in Erdmann, Journal (1832), XIV, 455. See for further
information on this bleaching process: Michaelis, in Poggendorff, An-

752 NOTES TO PAGES 189- 193

nalen, XVII, 633 (also Erdmann, Journal (1833), XVII, 219), in which
he precedes the bleaching by light by one of sulphur.

1 1 . Merck, in Buchner, Repertorium, XLVI, 8; Berzelius, Jahresbericht,

XIV, 324. “

12. Trommsdorff, Annalen der Pharmacie (1834), XI, 190.

13. Buchner, Repertorium fur die Pharmacie (1835), LI, 27.

14. Berberine is the yellow-coloring substance of the barberry bush.

15. Buchner, Repertorium fur die Pharmacie (1835), LIV, 371.

16. Journal de Pharmacie (1836), No. 12; Dingier, Polytechnisches
Journal (1837), LXV, 433.

17. Berzelius, in Jahresbericht iiber die Fortschritte der physischen
Wissenschaften, XVII, 300.

18. Chevreul, in Journal de chimie medicale (1837), p. 92; Dingier,
Polytechnisches Journal (1837), LXV, 63— ten essays (1837-54).

CHAPTER XIX

1. The style of writing Niepce with an accent was used by Nicephore
himself in his letters; Fouque also, in his work, La Verite sur l' invention de
la photographie, continued it. On the contrary, Niepce de Saint-Victor,
descendant of a branch of the same family, wrote the name “Niepce”
without accent in his own case as well as when referring to “Nicephore
Niepce.” Therefore, the family Niepce seemed to have laid very little
stress on the accent. Daguerre also, in his well-known pamphlet of 1839,
wrote “Niepce” without accent, which is another evidence of the lack of
importance attached to a uniform mode of spelling the name. The spell-
ing “Niepce” is sometimes found; it is wrong. The proper spelling is
“Niepce.”

2. The source material on Niepce most frequently used is Fouque, La
Verite sur Vinvention de la photographie (1867). In this work the archives
of the family Niepce and the correspondence and the contracts were pub-
lished, thus revealing the great contribution of Niepce to the invention of
photography. Another biography we owe to Ernest Lacan, who added
valuable biographical data in the periodical La Lumiere (1856), pp. 1 5 1 ,
154, 167, 179. Niepce’s correspondence with Lemaitre on his discoveries
was published in Brit. Journ. Phot. (1864), p. 531, and (1865), pp. 5, 44.
In 1925 Georges Potonniee published an exhaustive biography of Nic6-
phore Niepce, in his Histoire de la decouverte de la photographie (Paris);
Isidore Niepce also published a pamphlet, Historique de la decouverte im-
proprement nommee daguerreotype (Paris, 1841). Niepce’s son Isidore
donated a great number of his father’s letters to the museum at Chalon.
This was done at the time of the erection of the statue of the inventor on
one of the prominent places in Chalon on June 2 1, 1885. In the Bull. Soc.

NOTES TO PAGES 195 - 204 753

frang. de phot. (1913), p. 143, is the following genealogy of the family
Niepce.

Bernard Niepce, 1671 to 1766

Claude Ni6pce

Nicephore Niepce
1765 to 1833

Isidore Niepce
1805 to 1868

Bernard Niepce

Laurent Niepce
Married to
Mile de Saint-Victor

Abel Niepce de
Saint-Victor
1805 to 1870

3. S. Fouque, La Verite sur I'invention de la photographie (1867), p.
49 -

4. They are published in Fouque, La Verite sur I'invention de la photo-
graphie (1867).

5 . Bockmann is the first to note this, in 1 800; more exhaustive research
was undertaken by A. Vogel in 1812.

6. It is interesting to note that Poirson, in 1886, rediscovered this meth-
od of copying on a layer of phosphorus (on stone) and the fixation of the
image by red phosphorus with carbon disulfide.

7. I mention here the names of the later scientists: Senebier (1782),
Wollaston (1802), to whom I have previously referred, and others.

8. See an exhaustive essay by F. Paul Liesegang in Z entralblatt fiir Op-
lik und Mechanik (1930).

9. G. Cromer, Paris, procured in 1921 a letter from Nicephore Niepce,
dated May 26, 1826, in which he reports on his photographic experiments;
it is reproduced in facsimile in Bull. Soc. frang. d. phot. (1922), p. 71.

10. Fouque, La Verite sur I'invention de la photographie, p. 108; also
Chevreul, “La Verite sur I’invention de la photographie” (Journal de sav-
ants, 1873).

11. Isidore Niepce’s letter to Fouque, March 10, 1867, i.e., forty years
later (Fouque, p. 122).

12. It does not seem to be a mere accident that Nicephore Niepce used
just Dippel’s animal oil as a solvent (this oil is obtained from bones, by
dry distillation); it is more than likely that he was familiar with the ob-
servations of prior chemists on the light-sensitivity of this oil (Swindern
in 1805 and Link in 1808); it was not much later that the light-sensitivity
of this oil was recognized, with that of asphalt.

754 NOTES TO PAGES 205-210

1 3. Rapport du Comite d’ installation; Musee retrospect if de la Classe 12
Expo sit. universelle 1 poo (Paris, 1903), p. 11.

14. A Russian professor, N. E. Yermilow, reported in the Sow jet Pho-
to-Almanach for 1929 (Moscow) on a manuscript, written about 1828 by
Nic. Niepce, which he at that time sent to the Imperial Russian Govern-
ment; at present this letter is in the possession of the Soviet Academy of
Sciences, in Moscow. This letter contains an original report on Niepce’s
work and was published in English by Brit. Journ. Phot. (1930), p. 603,
under the title, “On Heliography, or a means of automatically fixing by
the action of light the image formed in the photographic camera obscura.”
This interesting MS contains nothing important or more illuminating than
our present knowledge of the subject.

CHAPTER XX

1. This “prisme menisque,” invented by the brothers Chevalier, was an
optical instrument consisting of a lens which was on one side concave
and on the other side convex.

CHAPTER XXI

1. For Daguerre’s biography see also Colson, Memoir es originaux des
createurs de la photographie (Paris, 1898); Blanquart-Evrard, La Photo-
graphie, ses origines (Lille, 1870); Mentienne, La Decouverte de la photo-
graphie en 1839 (Paris, 1892); in Poggendorff, Bio gr. -liter. Handworter-
buch zur Geschichte der exakten Wissenschaften (1863, I, 509), Da-
guerre’s date of birth is erroneously given as 1789.

2. The statement that Daguerre’s parents were peasants in Normandy
is incorrect.

3. Robert Fulton (b. 1765, in Little Britain, Pennsylvania, d. 1815)
built the first practical steamboat which sailed up the Hudson, in 1807.
He was a skilled goldsmith, went to London, was a mechanic, together
with Rumsey, traveled to Paris, where he constructed panoramas for
Barlow.

4. See Potonniee, Histoire de la decouverte de la photographie (1925),
p. 124.

5. In Bull. Soc. frang. de phot. (1924), p. 52. G. Cromer publishes
documents on the history of photography and reports particularly on the
“Artist Daguerre and his diorama” and on the painter Charles Maria Bou-
ton, Daguerre’s collaborator in this enterprise; Cromer’s statements are
based partly on Potonniee’s historical research; he stresses more exact data
on Daguerre’s career. We learn from this that Daguerre in his youth
worked for Degotti, the painter of scenes at the Opera in Paris. He also
created, with Ciceri, a famous landscape painter of his time, the decora-

NOTES TO PAGES 211-227 755

tions for the play “The Magic Lamp,” as well as various decorations for
the Ambigu Theater.

6. Mentienne, La Decouverte de la photographic en 1839 (Paris, 1892);
G. E. Brown, The Amateur-Photographer (1904), XXXIX, 41 1.

CHAPTER XXII

1. A “ligne” is a French unit of length =2. 2 56 millimeters.

2. This article was written in December.

3. This remark of M. Niepce was merely hypothetical, and experience
has shown that the achromatic camera obscura, although it made the
image more distinct, did not procure the perfect sharpness which M.
Niepce hoped to obtain. (Note by Daguerre.)

4. I want to call attention to the fact that the prints of which M. Niep-
ce speaks were produced by contact with copper engravings which were
placed in contact with the impregnated material. Also that the use of the
wax of which he speaks neutralized the action of the bitumen of Judea
solution in the camera obscura, where the action of the light was very
much diminished; the mixture with the wax, however, was not a serious
obstacle to obtaining his prints, because he exposed them for three to four
hours to the full sunlight. (Note by Daguerre.)

5. It is important to mention that M. Niepce’s use of iodine for black-
ening his plates proves that he had no knowledge of the property of this
substance to decompose when exposed to light in contact with silver. This
is also proven, because on the contrary he cites iodine as a means for the
fixation of his prints. (Note by Daguerre.)

CHAPTER XX1I1

1. Daguerre, Historique et description des procedes du daguerreotype
(1839).

2. Daguerre, who had no educational background in natural sciences,
was not familiar with Davy’s discovery of the light-sensitivity of silver
iodide in 1814.

3. Daguerre, Geschichte und Beschreibung des Verfahrens der Daguer-
reotypie und des Dioramas, translated from the original French into Ger-
man (Karlsruhe, 1839), p. 72.

CHAPTER XXIV

1. See A. Davanne, Nicephore Niepce, inventeur de la photographic;
conference faite a Chalon-sur-Saone, pour I’inauguration de la statue de
Nicephore Niepce, le 22 juin, 1885 (Paris, Gauthier-Villars, 1885).

2. This is a polemical pamphlet against Daguerre and emphasizes the

756 NOTES TO PAGES 230-253

claim of Niepce as the real inventor of photography; the pamphlet sharp-
ly criticizes the suppression of Niepce’s name in the publication of the
joint invention under the title “Daguerreotypy,” although the latter had
already permitted this in the agreement of 1837. Later, Isidore Niepce em-
phasized that he did this under the pressure of circumstances, because
Daguerre knew all Niepce’s secret process.

CHAPTER XXV

1. Daguerre, having demonstrated to Arago the results of his invention,
also showed them to the French physicist and astronomer John Baptiste
Biot (1774-1862) and to the famous German scientist, Alexander von
Humboldt, who at that time resided in Paris. The complete procedure was
confided only to Arago, the Secretary of the Academy of Sciences in
Paris. It was not until January 7th that Arago made his report to the Paris
Academy of Sciences.

CHAPTER XXVI

1. Compt. rend. (1839), IX, 250.

2. The members of this commission were Baron Athalin, Besson, Gay-
Lussac, Marquis de Laplace, Viscount Simeon, Baron Thenard, and
Count of Noe.

CHAPTER XXVII

1. Paris photograpbe (1891), p. 24.

CHAPTER XXV III

1. George E. Brown, in The Amateur Photographer, 1904, p. 41 1; an
illustrated article: “The Last Days of Daguerre; Some Notes on a Visit to
Bry-sur-Mame.”

2. Handbuch (2d ed., 1892), Vol. I, Part 1, Plate 1.

3. Bull. Soc. franp. (1897), pp. 308, 320.

CHAPTER XXIX

1. An original Daguerre-Giroux camera, which Eder acquired for the
collections of the Graphische Lehr- und Versuchsanstalt in Vienna in
1890, is at present exhibited in the Technical Museum, Section for Pho-
tography, in Vienna. Dost and Stenger, Die Daguerreotypie in Berlin,
1839-1860, 1922, also contains a good illustration of such a camera.

2. The well-known Paris optician Chevalier adapted Wollaston’s con-
cave-convex periscopic meniscus to the first lenses which he made for
Niepce’s and Daguerre’s experiments. Wollaston invented and described

757

NOTES TO PAGES 253-254

the fundamental principle of his invention on June 11, 1812, and em-
phasized the advantages of this type of lens over the former biconvex
lens. The concave side of the lens was turned to the object to be pho-
tographed. It was exactly this type of meniscus lens Chevalier chose for
the daguerreotype camera in 1839. He had pointed out the fact in several
addresses at the Societe d’Encouragement, Paris. The apparatus construct-
ed for the daguerreotype by Giroux, as well as the first Austro-German
lenses produced by Simon Plossl, of Vienna, followed this form of lens.
The achromatic single lenses Daguerre had used earlier usually had an
aperture of three inches and about sixteen-inch focus; this opening, how-
ever, was reduced to one inch by placing a diaphragm in front of it at a
distance of three inches. Daguerre frequently exposed with two-inch
lenses, in 1839, for about ten to twenty minutes. At this time Townson
had already suggested the use of a lens of a greater diameter and a more
precise correction of the focal distance in order to eliminate the chromatic
aberration. It is these lenses that Draper used for his portraits, in New
York, in 1840. These portraits, taken with enormously long exposure,
were not sharp, owing to the imperfection of the lens and the inevitable
restlessness of the sitters. For Chevalier’s lens, see M. von Rohr, Theorie
und Geschichte des photographischen Objektivs (1893), p. 89.

3. At first only silvered copper plates were used; since 1845 the less
expensive copper plates on which the silver had been deposited by the
galvano process were found usable. The Berlin chemist A. Lipowitz of-
fered in his book Die Daguerreotypie (1845) a process for the production
of such plates for five thalers (Wilh. Dost. Phot. Chronik, 1925, p. 391;
see also Kilbum, Phot. Magaz., XXXII, 541; Fortschr. d. Physik, 1848, p.
196; Boue, Compt. rend., XXIV, 446). In some cases silver foil mounted
on cardboard was used for the production of daguerreotypes (Raife,
Compt. rend., 1840; Dingier, Journ., LXXVII, 159).

4. For further details see Eder and Kuchinka, Die Daguerreotypie
(1927). Handbuch, Vol. II, Part 3.

5. Musee retrospectif de la Classe 12, Photographie. Rapport du Comite
d'installation (Paris, 1903).

6. Sir John Frederick William Herschel, b. 1792, d. 1871, in London,
son of the famous astronomer Friedr. Wilhelm Herschel, who died in
1822, devoted himself first to the study of astronomy and optics; later he
engaged in chemical and physical experiments and also gave some time to
photochemical investigation.

7. Many years later it was said that Herschel had forgotten his twenty-
year-old observation on the solubility of chloride of silver in sodium
hyposulphite. But it was published in W. T. Brande’s Chemistry and that
is where Joseph Bancroft Reade found it in 1839 while he was engaged

758 NOTES TO PAGES 254-270

in photographic research. He had the apothecary Hodgson of the Apoth-
ecaries Hall, in London, prepare some sodium hyposulphite for him. He
successfully experimented in fixing silver chloride paper images and in-
formed Herschel of it. The latter originally used hyposulphite of am-
monia as the fixing agent; but then he adopted Reade’s sodium salt. This
chemical thereafter became generally used under the name “fixing so-
dium.” This was reported in Phot. Journ., 1928, pp. 305-1 1, with Reade’s
portrait. There is at this time no way of verifying this belated story.

8. Hippolyte Louis Fizeau (b. 1819, in Paris, d. 1896), together with
Foucault and other scientists, was engaged in experiments in physics;
after 1843 he successfully turned to photography, which owes to him
many improvements.

9. The earlier history of the panorama camera is (with many illustra-
tions) published in the first edition of Eder’s Handbuch (1884), p. 412.

CHAPTER XXXI

1. In the early period of the daguerreotype the latent image was called
the “dormant image.”

2. This experiment of Draper is, however, proof only that no free
iodine escapes; yet it is separated, changing to metallic silver in the inner
stratum.

3. Compt. rend., 1843, XVI, 25; XVII, 4.

4. L. Lewandowsky, a student at the Polytechnikum, in Vienna, in-
vented, in 1843, his “iodine-and-exposure-meter” for daguerreotype,
which permitted the correct control of the iodization and proportionate
exposure ( Handbuch , 1930, Vol. Ill, Part 4). Later, Claudet’s “photo-
graphometer” (1848) is also described in the same place.

5. Here should be mentioned the magic photographs by W. Grime, in
Berlin, produced by the smoke of a cigar containing ammonia (1866).

6. E. Becquerel, when only nineteen years old, described a method for
an electrochemical actinometer (Compt. rend., 1839, p. 145).

7. For the Becquerel phenomenon and its importance for modem pho-
tochemical research see Luppo-Cramer, Handbuch (1927), II ( 1 ), 315. The
photographical “Becquerel-phenomenon” occurs also in silver bromide
gelatine; see Luppo-Cramer, Die Grundlagen deer photographischen Neg-
ativverfahren, 1927, p. 285 (Vol. II(i) of the Handbuch). See also Erich
Stenger, Z eitschr f. wissensch. Phot. (1930), XXIX, 44.

8. Compt. rend., XXIII, 679; Fortschr. d. Phys., 1846, p. 235.

9. Philos. Magaz., XXXII, 199.

10. Phot. Korr., 1874, p. 68; Fortschr. d. Physik, 1874, p. 507.

1 1. Pohl, Phys.-chem. Notizen, II series, p. 19.

12. E. Arago, Astronomie populaire (1855), Vol. II, Book xiv, chap. 22.

759

NOTES TO PAGES 271-276

CHAPTER XXXII

1. John William Draper, M.D. (b. May 5, 1811, near Liverpool, Eng-
land). Since 1836 professor of chemistry and physics at Hampden Sidney
College, Va., later (1839) professor at New York University. He died in
1882. See biography with portrait in The American Journal of Photog-
raphy (1861), p. 238; also Phot. Times (1882), p. 1.

2. Harrison, History of Photo gr. (1888), p. 26.

3. An illustration of the first daguerreotype camera constructed in the
U. S. A. is found in American Photography (1911), p. 516. This camera
is now in the photographic section in the National Museum, Washing-
ton, where numerous other photographic incunabula are collected. These
are, for instance, two daguerreotypes made in 1839 by the inventor; a
heliograph by Niepce, of 1824; a silverprint by Fox Talbot, of 1839; and
other documents of the development of photography. The different pro-
cesses are not only represented by the results but also shown by specimens
of the apparatus by which they were produced. There are about 250
apparatus, which make it possible to study almost every step in the prog-
ress of construction from the beginning. The collection was started in
1876, and it is surprising to find it much more extensive than similar ones
in Europe which had only been begun in the course of the last decades
(Phot. Ind., 1911, No. 39, p. 1358; Phot. Korresp., 1911, p. 637).

4. In 1840 W. Draper, of New York, stated that it is possible to make
portraits in full sunlight, using mirrors as light reflectors. “But in the re-
flected sunshine, the eye cannot support the effulgence of the rays. It is
therefore absolutely necessary to pass them through some blue medium,
which shall abstract from them their heat and take away their offensive
brilliancy. I have used for this purpose blue glass, and also ammoniaco-
sulphate of copper, contained in a large trough of plate glass, the inter-
stice being about an inch thick” ( Philosoph , Magaz., Sept., 1840, p. 217;
Dingier, Polytechn. Journ., LXXVIII, 120).

5. Werge, The Evolution of Photography (1890), p. 79. J. F. Sachse
erroneously confuses Dr. Paul Beck Goddard, professor at the University
of Pennsylvania, who occupied himself somewhat with daguerreotypy,
with the inventor of the iodo-bromide plates, John Frederick Goddard
(Jahrbuch f. Phot., 1894, p. 258). Werge published John Frederick God-
dard’s portrait in his The Evolution of Photography, p. 27; one of Dr.
Paul Beck Goddard is to be found in American Journal of Photography
(July, 1883), p. 308.

6. According to his contemporary Berres, in Vienna (Dingl. Poly-
techn. Journ., 1841, LXXXI, 151).

7. Wiener Zeitung, January 19, 1841, p. 139.

8. One of the brothers, Johann Natterer, M.D. (1821-igoo), was the

760 NOTES TO PAGES 277-288

inventor of the compression pump for the liquefaction of carbonic acid
and was well known in the history of chemistry. (Cf. Natterer’s biog-
raphy by A. Bauer, published in the Cbemiker Zeitung, 1901; also Jahrb.
f. Phot., 1891. The Viennese geologist Professor Ed. Suess (president of
the Academy of Science) was a brother-in-law of the brothers Natterer.

9. J. M. Eder donated these originals from his own private collection
to the Graphische Lehr- und Versuchsanstalt in Vienna.

10. Rapport du Comite d’installation Musee retrospectif de Photogr.
Exposition universelle Paris 1900 (issued 1903).

11. For instance, Claudet’s publications on iodo-bromide of June 10,
1841 ( Philosoph . Magaz., 1841, 3d ser., XIX, 167), are credited unjustly
by some authors with the priority of the introduction of the combina-
tion of bromide with iodine for the sensitization of silver plates.

12. Must not the outstanding celebrated scientists be recognized as in-
contestable witnesses?

13. Charles R. Gibson, in Chapter I, “The History of Photography,”
of the work entitled Photography as a Scientific Implement, 1923, p. 30
(German translation by Alfred Hay, pub. by Fr. Deuticke, 1929, p. 23)
writes: “The daguerreotype plates were made more sensitive b y the ap-
plication of bromine, which was added by Goddard in 1 840; this was en-
hanced further by Claudet’s introduction of chlorine along with iodine.”
He does not mention Kratochwila and the Natterer brothers. Evidently
he was unfamiliar with the technical literature of 1840, and on the whole
he seems to write very objectively.

CHAPTER XXXIII

1. E. Stenger, Camera, 1930, VIII, 193.

2. From 1815 Prechtl was director of the Polytechnische Institut,
Vienna, which he organized and over which he presided until 1849. The
Technologische Enzyklopddie (20 vols., 1830-1855), edited by him, is
well known. Also his Praktische Dioptrik, which he published in 1828, is
of interest for us. He promoted photography and photographic optics.

3. Conventionsmunze: 20 gulden conventionsmiinze= 1 o thaler (1 thal-
ler equals 3 German marks).

4. The Waldstein family of opticians appears first in Arnold Wald-
stein (b. Wurtemberg, 1787; d. Vienna, 1853). He was an optician in
Munich and founded there a factory for grinding glass; he met Fraun-
hofer and opened a branch office in Vienna in 1842 (see biography of the
Waldstein family in Osterr. Zentralzeitung f. Optik. u. Mechanik, 1927,
No. 10).

5. Phot. Korresp., 1908, p. 578.

6. Abstract, Journal of the Franklin-Institute, October, 1908, p. 315.

76t

NOTES TO PAGES 290-291

CHAPTER XXXIV

1. Dr. Otto Waldstein, Osterr. Zentralzeitung f. Optik u. Mechanik,
1926, No. 14.

2. See footnote 3 for Chapter XXVIII.

3. Dr. Ermenyi published in Phot. Zentralblatt (VIII, 247) an exhaus-
tive biography of J. Petzval. See also his Petzvals Leben und Verdienst
(1903). Until then little was known about him. Even the date of his
birth was disputed; in the obituary Professor E. Suess in the Imperial
Academy of Sciences, Vienna (Petzval was a member of the Imperial
Academy of Sciences), called attention to the contradictory available
data (Almanack Wien , kais. Akad. d. Wiss., 1892, XLII, 182). But the
data given by Eder proved to be correct. Eder mentioned several times
that it was Petzval himself who, emphasizing the fact that he was the son
of German parents, had made him put down in writing explicitly the day
and year of birth, namely, January 6, 1807; this date, which Eder had also
published in the first edition of his Handbuch der Photographie (1(2), 40),
had been doubted by some persons, since there exists documentary evi-
dence that January 6, in other years, is also the birthday of his two broth-
ers; it was held to be most improbable that all three sons of one family
were bom on the same day of the year, on Epiphany. But Dr. Ermenyi’s
research, made in Petzval’s city of birth itself, in Szepes-Bela, District of
Zips, Hungary, confirmed that in the parochial vital statistics Petzval’s
date of birth was registered as January 6, 1807; thus this question is settled
for good. Among friends the three brothers Petzval had the nickname
“The Three Magi,” alluding to their birthday January 6. Dr. Ermenyi
publishes in his Petzval biography, a work worthy of highest apprecia-
tion, various authentic facts of Petzval’s life and his scientific work (Phot.
Korresp., 1902, p. 395). For Petzval’s work on the subject of optics see
also M. von Rohr, Theorie und Geschichte des photogr. Objektives,
(1899). Zips, in the former Austro-Hungarian monarchy, was a Hun-
garian county in Northern Hungary on the Galician border, with a mixed
population and some German settlements. After World War I, when
Austria-Hungary was dismembered, it was assigned to Czechoslovakia,
together with the most beautiful parts of the High Tatra.

4. Joseph Petzval correctly remarked, in his Bericht iiber die Ergebnis-
se einiger dioptrischer Vntersuchungen (1843, p. 26): “Lens combina-
tions are quite moody and refractory objects, which, when placed in a
certain rotation, do not produce at times any kind of a decent image,
sometimes an inevitably crooked or distorted one; this is entirely due to
general basic laws which are deeply seated in the construction of their
complicated functions. . . . The practical scientific optician will reach the

762 NOTES TO PAGES 292-303

peak of his art only through the closest kind of an association with intense
research in the science.”

5. Akademiker Dr. Petzval beleuchtet vom Optiker Voigtlander,
Brunswick, 1859.

6. A study, important for the history of optics, is Harting’s “Zur Ge-
schichte der Familie Voigtlander, ihrer Werkstatte und ihrer Mitarbeiter”
(Central-Zeitung fur Optik und Mechanik, 1924/25). This study was
also published as a separate pamphlet by Aktiengesellschaft Voigtlander
& Sohn, (Brunswick, 1925). M. von Rohr has added to this significant
essay valuable source material; in the Zeitschrift fur lnstrumentenkunde
( 1925, XLV, 436, 470) he gave a summarizing account of the Voigtlander
optical workshop and its environment. An excerpt of it by F. P. Liese-
gang is published in Centralzt. f. Opt. u. Mech. (1926).

7. The illustration of this medal in the 1932 edition of this History was
reproduced from the collection of medals awarded to the author.

8. See Claudet’s later essays ( Compt. rend., October 1 8 and December
20, 1847, and 1851, XXXII, 130); also Recherche s sur la theorie des prin-
cipaux phenomenes de photographie (Paris, 1849); Nouvelles recherches
sur la difference entre les foyers visuels et photo genique et sur leur con-
st ante variation (Paris, 1851); and Claudet’s report in Revue photograph-
ique (1857), p. 250.

9. These first Petzval-Dietzler portrait lenses, constructed under Petz-
val’s supervision, were excellent and were used successfully in first-class
portrait studios in Vienna until the end of the nineteenth century; an old
Dietzler objective was continually used for half-length portraits in the
portrait studio of the renowned photographer Dr. Szekely, Vienna, hold-
ing its own during the collodion method and until that of silver bromide
gelatine. The author witnessed these changes. He also started a collection
of good Dietzler lenses at the Graphische Lehr- und Versuchsanstalt,
Vienna.

10. At that time, beside the Viennese optician Dietzler, other profes-
sionally skilled opticians established themselves who also copied portrait
lenses, such as Eckling, Prokesch, Waibl, and Weingartshofer; Kuchinka
reports on that exhaustively in his “Geschichte der photographischen Op-
tik in Wien” (Phot. Korr., 1927).

11. See Dr. L. Ermenyi, “Theorie der Tonsysteme von Petzval,” in
Zeitschr. Math. u. Physik (Vol. LI); also Petzval’s work on the Theorie
der Schwingungen gespannter Seiten (1858).

12. Ermenyi’s writings, in chronological order, are: “Dr. Josef Petz-
vals Leben und wissenschaftliche Verdienste,” Photo graphisches Zen-
tralblatt, 1902, VIII, 247-278; Dr. Josef Petzvals Leben und Verdienste,
2d ed., essentially enlarged, with eleven pictures and two figures (1903).

NOTES TO PAGES 303-314 763

“Nachtragliches iiber Petzval,” Photo graphisches Zentralblatt, 1904, X,
239-245. See also M. von Rohr, “Uber altere Portratobjektive,” Z eitschr.
f. htstrumentenkunde (1901), XXI, 49; M. v. Rohr, “Die optischen Sys-
teme aus Petzvals Nachlass,” Phot. Korresp. (1906), p. 266; J. M. Eder,
“Petzvals Orthoskop,” in his Jahrbuch (1900), XIV, 108.

13. See Phot. Korresp. (1902), p. 756. Eder, Jahrb. f. Phot., (1904),
p. 249.

14. Until now it has been only once awarded, namely, at the end of
Eder’s honorary year of service as professor at the Technische Hochschu-
le, when he was 70 years of age (1925). The “Staatliche Lichtbildstelle”
was, after the breakdown of Austria, no longer a state institution and was
continued as “Osterreichische Lichtbildstelle.”

15. Friedrich’s death urged W. F. Voigtlander to establish a Voigtland-
er-Foundation of the Viennese Photographic Society. A portrait of
Friedrich taken by A. Mutterer is in the collection of the Graphische
Lehr- und Versuchsanstalt, Vienna.

1 6. Collection of the Wiener photographische Gesellschaft.

17. See also Rohr, Zeitschr. f. Instrumentenkunde (1925), XLV, 436,
470; (1926), XL VI, 76.

18. This lens was one of the chief attractions at the Miinchener Ge-
werbeausstellung in December, 1819, and brought to the manufacturer a
medal, awarded on that occasion for the first time.

19. The way the production of these Benediktbeurener lenses came
about was as follows: Georg von Reichenbach established, in 1804, to-
gether with Utzschneider and Liebherr, a mechanical institute. Then, in
1809 Reichenbach founded, with Fraunhofer and Utzschneider, in Bene-
diktbeuren, the optical institution which became so famous. It was in this
institution that Fraunhofer ground and produced the lenses.

20. Professor Ernst Voit, Munich, published, with Dr. Adolph Stein-
heil, the Handbuch der angewandten Optik (1891).

21. A. Rogers was an astronomer at Harvard University, Cambridge,
Mass. From 1877-1886 he was observer. Later he was professor of astron-
omy and physics at Colby College, Waterville, Me.

22. The British patent No. 329144, of May 3, 1929, registered' by A.
Warmisham and Kapella for modified “Petzval-Cine-Lenses” of the
enormous intensity of light f/1.8 proves that Petzval’s masterly achieve-
ment in constructing his portrait lens was the incentive for calculating
objective constructors far into the twentieth century.

CHAPTER XXXV

1. Dernier s perfectionnements apportes au daguerreotype, by Gaudin
and Lerebours (3d ed., Paris, 1842).

764 NOTES TO PAGES 314-323

2. Traite de photographie, dernier s perfectionnements apportes au da-
guerreotype, by N. P. Lerebours (Paris, 1843).

3. Traite de photographie, by Lerebours and Secretan (5 th ed., Paris,
1846).

4. Prints made in the studios of Lambert, Paris, Lerebours and Secre-
tan, Paris, of the painter Martin Theyer, Vienna, are in the department of
mechanical technology at the Technische Hochschule, Vienna; other
large collections of early daguerreotypes are in the Graphische Lehr- und
Versuchsanstalt and in the Technisches Museum, Vienna.

5. In the collection of the Graphische Lehr- und Versuchsanstalt,
Vienna.

CHAPTER XXXVI

1. Instructions for the coloring of daguerreotypes published in the
Neueste Ratgeber fur Daguerreotypie (see Lerebours), 4th ed., Leipzig,
Fr. Volkmar, 1843.

2. Dingier, Polytechn. Journ., LXXXVII, 316.

3. Martin, Repertorium der Phot. (1846-1848), II, 98. Martin, Hand-
buch d. Phot. (1854), p. 296.

CHAPTER XXXVII

1. Poggendorff, Biograph, liter arisches Handworterbuch (1863) II, 1066.

2. C. H. Talbot, Talbot’s son, lived there in 1905. The author owes to
his kindness three very beautiful Talbot copper heliogravures.

3. Compt. rend. (1839), VIII, 341.

4. Seventy-five years later potassium ferrocvanide was discovered as a
fixing agent by N. Sulzberger, who took out a German patent. Eder
proved that this was nothing new and that it was invented by Talbot and
published in Compt. rendus (1839), p. 341. See also E. Valenta, Phot.
Korresp. (1916), p. 199, and Eder, Jahrbuch (1916), p. 415.

5. Dingier, Polytechn. Journ., LXXXI, 356, 363; Philosoph. Magazin
(1841), p. 88. A pamphlet was published on Talbot’s calotype process:
Lichtbilder (Portrdts) auf Papier in ein bis zwei Minuten darzustellen, von
Talbot, Physiker in London (Aachen, 1841).

6. William Henry Fox Talbot applied for the grant of a patent for his
invention of the Calotype process in England on February 8, 1841; it was
signed on July 29, 1841, and sealed on August 17 of the same year. The
Liverpool Photographic Journal published it exhaustively in 1857, p. 114,
as a historically important document. It was reprinted from there in
other periodicals (for instance, Dingier, Polytechn. Journ., LXXI, 468).

7. Waxing of papers. Repert. of pat. invent., January, 1844, p. 47;
Dingier, Polytechn. Journ., XCII, 94.

NOTES TO PAGES 325-330 765

8. Phot. Archiv (1877), p. 169. Camera obscura (1901), II, 840; also
British Journ. of Phot. (1877)

9. This is, moreover, inadmissible, because Reade obtained images only
with silver nitrate and gallic acid. The method of developing the latent
image, later discovered by Talbot, refers, however, to the image pro-
duced with silver iodide, silver bromide, or silver chloride.

10. Encyclopaedia Britannica, 8th edition, article on “Photography,”
p. 545; also published in Harrison, History of Photography (1888), p. 31,
and copied without giving the source in Schiendl, Geschichte der Photo-
graphie; John Werge treated this work exhaustively in his Evolution of
Photography (1890), where he reproduced also a portrait of Reverend
J. B. Reade, who died December 12, 1870. See also Brit. Journ. Phot. Al-
manac , (1931), p. 156.

11. Blanquart-Evrard, Traite de photographie sur papier (Paris, 1851).

12. Published in the Comptes rendus, XXIV, 117; Dingier, Polytechn.
Journ., CIV, 32, 275; CVI, 365; CVII, 193. Martin, Handbuch der Photo-
graphic (1851), p. 187; proven formula by Martin, see Martin, Handbuch
d. Phot. ( 1865), p. 281. See Eder’s Handbuch ( 1927), II, 3.

13. Dingier, Polytech. Journ., XCII, 367, from Philos. Magaz. (1844).
Martin, Handb. d. Photographic (1851), p. 201.

14. Le Gray, Photographic (1852), p. 24.

15. Journ. Phot.Soc. (London, 1856), p. 65; Kreutzer, Jahrb. Photogr.
(1856), p. 19. Later, Parr found that it is best to treat the silvered paper
with sodium acetate (formation of silver acetate).

16. Blanquart-Evrard, Procedes employes pour obtenir les epreuves de
phot, sur papier (1847); Traite de phot, sur papier (1851); and other
publications.

17. Thomas Sutton was an accomplished English photographer, dis-
tinguished also by numerous publications in technical journals. He wrote:
T he Calotype Process; a Hand-Book to Photography on Paper (London,
1st ed., 1855; 2d ed., 1856). Sutton and Dawson, A Dictionary of Photog-
raphy (London, 1st ed., 1858; 2d ed., 1867). This publication and others
are good descriptions of the state of photography of the time.

18. The apothecary A. Moll, Vienna, started the manufacture of chem-
icals for photography in 1854.

19. Anastas Jovanovits, b. 1817, in Bulgaria, was at one time High
Steward of Prince Michael Obrenowitz of Serbia, assassinated in 1868. He
lived mostly in Belgrade, often visited Vienna, where he died in 1899, 82
years old. He was one of the first amateur photographers who had be-
come familiar with photography around 1840 in Vienna through the
librarian Martin; later he introduced photography into Serbia and Mon-
tenegro (Phot. Korresp. (1899), p. 731).

7 66 NOTES TO PAGES 330-335

20. A portrait of Regnault, see Pector, Notice historique, (Paris,
1905).

21. See La Lumiere (February, 1851), p. 3.

22. Dingier, Polytechnisches Journal, CXXIII, 158.

23. See Eder, Phot. Korresp. (1891), pp. 153, 256.

CHAPTER XXXVIII

1. “Elies resultaient de ce que l’image etait combinaison d’argent et
d’acide gallique” (Blanquart-Evrard, La Photographie, ses origines . . .
1870, p. 187).

2. The Library of Lille has supposedly a copy (Blanquart-Evrard, La
Photographie, ses origines . . . 1870, p. 187). I saw only one page of it.

3. In 1854 Blanquart-Evrard was already in a position to publish a re-
markable catalog of his photographic art publications; this firm, however,
does not seem to have existed very long.

CHAPTER XXXIX

1. See Bull. Soc. franp. d. phot. (1887), pp. 167, 174; see also Colson,
Memoir es originaux des creatures de la phot. (Paris, 1898).

2. In 1839 Fyfe had also discovered the good qualification of silver
phosphate for photographic copying paper. He treated paper either suc-
cessively with a solution of sodium phosphate and silver nitrate or pre-
pared it with a solution of silver phosphate in ammonia or ammonia car-
bonate. Fyfe fixed the photographs thus made with ammonia (Edinb.
New Philos. Journ. (1839), p. 144; Dingier, Polytechn. Journ., LXXIV,
55; Eder, Handbuch (1887), IV, 6, 34). He produced also photographs
on canvas by this process. M. Lyte used silver phosphate also on albu-
minized paper and fixed with diluted nitric acid (Journ. Phot. Soc., Ill,
50; Kreutzer, Jahrb. f. Phot. (1856), pp. 27, 28; (1857), p. 58).

In 1844 Hunt mentioned that photographs on silver-phosphate paper
are well suited for development with gallic acid + silver nitrate (see Eder,
“Photochemie,” Handbuch, 1906, 1(2), 302; see also Eder, “Silberko-
pierverfahren,” in Handbuch, 1896, Vol. IV). Johann Meyer, Brooklyn,
applied it successfully in the “printing-out” process (Brit. Journ. Phot.,
1899, pp. 714, 721; 1900, pp. 132, 134; Eder, Jahrb. f. Phot., 1900, pp. 636,
1901, p. 660). E. Valenta (Eder, Jahrb. f. Phot., 1901, p. 130) described
the use of silver phosphate colloidine paper without silver chloride
(“printing-out” process); the result produced beautiful, durable papers,
which are exhibited in the technical museum in Vienna (photography
section).

3. This refers primarily to the photochemical decomposition of the
potassium iodide, which shows its greatest effect in the short-wave spec-
trum.

NOTES TO PAGES 336-339 767

CHAPTER XL

1. E. Stenger publishes a more extended biography of A. Breyer in
Phot. Ind. (1926), p. 155. Friedrich Wilhelm Breyer’s father, b. 1787,
in Hirschberg, Upper Silesia, Germany, studied medicine in Berlin. His
eldest son, Albrecht Breyer (b. October 16, 1812, in Berlin, d. August 9,
1876, in Brussels) studied medicine in Liege; he graduated there in 1839
and moved later to Brussels, where he practiced as general physician, sur-
geon, and obstetrician. He never again referred to his earliest publication
on the process of copying of opaque objects. He died August 9, 1876, in
Brussels.

2. The typon process is the recent application of this method.— Note
by William Gamble.

3. Invented by Max Ullmann, of Zwickau (Sacheen), in 1913 (Hand-
buch, 1922, IV(3), 387).

CHAPTER XLI

1. Niepce de Saint-Victor used no accent on the first “e” in his name, as
mentioned in Chapter XIX.

2. Compt. rend. (Oct., 1847), XXV, 586, and XXVI, 637; Dingier,
Journ., CVII, 58, and CIX, 48; Jahrb. f. Chemie (1848), p. 232.

3. Gehlen (1804) discovered the light-sensitivity of uranium chloride
in alcoholic solution. Burnett, an Englishman, invented, 1857, a photo-
graphic process of copying on paper which was impregnated with urani-
um nitrate; he recognized the photochemical reduction of uranous salt
(also tartaric acid and citric acid uranous salt) to oxide (uranous salt),
the copies were made visible, among other ways, by treatment with sil-
ver nitrate or potassium ferricyanide (Photogr. Notes, 1857, p. 97, see
also Handbuch 1927, IV(4), 159, under “Lichtpauserei”). Only later, in the
period between 1858 and i860, Niepce de Saint- Victor also engaged in the
process of copying by means of uranium. Niepce de Saint-Victor elaborated
on this basis processes of copying photographs (submitted to the French
Academy of Sciences in March, 1858), having, however, the earlier pre-
liminary work of Burnett, of 1857, at his disposal. The articles of Niepce
de Saint-Victor on the photographic application of uranium salt (1858-
1860) were published in the Compt. rend., XLVI, 448, 449; XLVII, 860,
1002; XL VIII, 470; XLIX, 815; in German, Dingier, Polytechn. Journal,
CXLVIII, 126; CLI, 130, 435; CLVI, 456.

4. Compt. rend. XXIX, 215; Annal. Chem. und Pharmac., LXXII, 179.
Dingier, Journ., CXIV, 123. For other modifications see Blanquart-
Evrard, Traite de photogr. (1851). The spelling “Blanquard” is wrong;
“Blanquart” is correct.

768 NOTES TO PAGES 339-346

5. From the Greek “amphi”=both, because the image appears positive
on one side and negative on the other.

6. Compt. rend., XXXVII, 305.

7. Le Gray, Traite, newed., p. 117.

CHAPTER XLll

1. Annal. chim. phys., LII, 290; Poggend., Annal., XXIX, 176.

2. Poggend., Annal., LXX, 320; Compt. rend., XXIII, 678; John,
Chem. Schrift., IV, 204.

3. Ibid.

4. Compt. rend., XXIII, 808.

5. Handworterb. Chem. (1854), VI, 724.

6. Compt. rend., XXIII, 980, 1099; Journ. f. prakt. Chem. (1847), XL,
193, 418.

7. Pelouze, Compt. rend., VII, 713; Journ. f. prakt. Chem., XVI, 168.

8. Bley, Compt. rend., XXIII, 809; Bonjeon, Compt. rend., XXIV, 190.

9. Payen, Compt. rend., XXIII, 999; XXIV, 81.

10. Domonte and Menard, Compt. rend., XXIII, 1087; XXIV, 87, 390;
abstract, Journ. f. prakt. Chemie. (1847), XL, 421.

11. Louis Menard wrote a booklet, De la moral avant les philosophes
(i860), in which he refers (p. 104) to the mythology of the ancient
Greeks and suggests: “At that time one was not more annoyed with the
thousands of hymns to Zeus and Aphrodite than one is nowadays, when as-
suming that oxygen had become immoral because of its union with all
elements.”

12. Schiendl, Geschichte der Photographie, 1891 (see also the criticism
of this work in Phot. Korresp., 1891, pp. 148, 254).

1 3. The popular spelling “Legray” is wrong.

14. Aside from the book mentioned, Gustave Le Gray wrote also
Traite nouveau theorique et pratique (1853; 2d ed., 1854).

15. Also Snelling, Phot. Journ. (1857), p. 256; Kreutzer, Jahrber. f.
Phot. (1857), p. 506. It was Archer who first obtained beautiful effects
on collodion negatives through treatment with chloride of mercury
(Horn, Phot. Journ., XV, 36). To him is also due the credit for the in-
vention of the chemical intensification of the collodion negatives. Archer’s
earliest writings are published in Chemist (1851), Athenaeum, La Lumifre
(1851 and 1852), Humphrey’s Journal (1851 and ff.), and others.

16. Revue photogr. (1857), II, 207; Kreutzer, Jahrber. f. Phot. (1857),
p. 506.

17. Belloc, Les Quatre Branches de la phot. (Paris, 1858), p. 165.

18. Bingham’s letter to La Lumiere of 1854; Horn, Phot. Journ. (1854),
E 43-

NOTES TO PAGES 346-358 769

19. Compt. rend. (May, 1854), No. 19; Dingier, Polyt. Journ., CXXV,
28.

20. H. W. Vogel, Die Photographie auf der Londoner Weltausstellung,
(1863), p. 32.

21. Millet, Cosmos (March, 1854), p. '261; Dingier, Polyt. Journ.,
CXXXI, 467. Nevertheless, Glover and Bold, of Liverpool, secured a
patent on the identical process on February 20, 1857 (Dingier, Polyt.
Journ., CXLVII, 157).

22. La Lumiere (1856), p. 16. Kreutzer, Jahrber. f. Phot. (1856), p.
188.

CHAPTER XL1II

1. Paris photo graphe (1892), p. 329.

2. Ibid., p. 328.

3. H. P. Robinson, Pictorial Effect in Photography (London, 1869)
with specimen illustrations; Robinson, Picture Making by Photography
(London and New York, 1884); Robinson, Art Photography in Short
Chapters (London, 1890). A portrait of Henry Peach Robinson will be
found in The Photographic Times (1897), p. 255; also his autobiography,
p. 497.

4. See H. P. Robinson, Yearbook of Phot. (1871).

5. Horn, Photogr. Journ. (1856), V, 88; VI, 7.

6. Read before the London Photogr. Society on December 15, 1859.

7. Bruno Meyer, Phot. Korresp. (1895), p. 442.

8. Disderi, L'Art de la photographie; avec une introduction par Lafan
de Camarsc. (Paris, 1862). Disderi, Die Photographie als bildende Kunst,
German translation by Weiske (Diisseldorf, 1864).

9. In the memoir Die Geschichte der Firma Ed. Liesegang (Diisseldorf,
1929), p. 8.

10. J. M. Eder, “Blaues Licht fur Portrataufnahmen bei kiinstlichem
Lichte; Vorschaltung von Kobaltglasem usw. in der Atelier-beleucht-
ung,” Die Kinotechnik (1929), XI, 259.

1 1. Claudet claimed priority for the use of backgrounds in daguerre-
otype photography (see Brit. Pat. No. 9193, for 1841).— Note by Wil-
liam Gamble.

CHAPTER XLIV

1. See also E. Stenger, Der Landschaftsphotograph und seine Arbeits-
behelfe zwischen i860 und 1880, reprinted from Matschoss, Beitrdge zur
Geschichte der Technik und Industrie (1930).

2. It is remarkable that in 1930 Willesden constructed a camera especi-
ally for amateur flyers, the “Pistol Aircraft and General Utility Camera”;

770 NOTES TO PAGES 360-371

the camera was made entirely of metal and used as a matter of course
all the advantages of dry plates (Brit. Joum. Phot. (1930), p. 107).

3. Hardwich’s successor at King’s College was Thomas Sutton, and
after him George Dawson. Sutton, an outstanding photographic expert,
was a successful experimenter and technical writer. With Dawson he
published the Dictionary of Photography (London, 1858; 2d ed., 1867).
As an author he wrote, probably the first photographic novel, which ap-
peared from January 1, 1865, serially in the Photographic Notes, the or-
gan of the Photographic Society of Scotland and Manchester, which
Thomas Sutton had edited from its beginning in 1856.

4. A purple artificial dyestuff made from uric and nitric acids and sub-
sequently treated with ammonia was discovered by Liebig and Wohler
in 1839.

5. Eder, “tJber die Einwirkung von Ferrizyaniden auf metallisches
Silber,” Journal f. prakt. Chemie (1877); previous excerpt in Chem. Z en-
tralbl. (1876), p. 569. Eder’s equation of reaction is as follows:

Ag 4 + 4Fe(CN) 9 K 3 = 3 Fe(CN) 8 K 4 + Fe(CN) 8 Ag 4
or

Silver + potassium ferricyanide = potassium ferrocyanide silver fer-

rocyanide.

6. Rutherford and Seely, in Seely, Am. Journ. of Phot., II, 251. Kreutzer,
Z eitschr. f. Phot. (1861).

7. “Sabatier,” as it is frequently spelled (also in Potonniee, Histoire de
Phot.), is incorrect.

8. Eder reports this in detail in Handbuch der Phot. (1884), II, 20, as
well as in the new edition of his Photographic mit Bromsilber gelatine.

9. To produce such secret writing the negative of a landscape with a
cloudy sky was copied on silver bromide gelatine card, then developed
and washed; after this the secret writing was copied on the white part of
the sky and immediately fixed. Thus the secret writing remained invisible
and latent. It could only be developed physically.

CHAPTER XLV

1. From the Greek 7»e/a=black. In this category belong the collodion
prints on blackened glass or collodion-development-images, which when
viewed appear, owing to the black layer, on the back as positives.

2. From the Latin ferrum (iron).

CHAPTER XLVl

1. Poitevin, Bull. Soc. frang. d. phot. (1863), p. 306.

77i

NOTES TO PAGES 373-380

CHAPTER XLV11

1. Compt. rend. (1855), XLI, 383; La Lumiere (September 8, 1855).

2. In 1853 Krone published Album der Sachsischen Schweiz (36 pho-
tographs in quarto) which attracted attention. This was commemorated
in 1857 by a tablet on the Basteibriicke (Stenger, Phot. Rundschau, 1931,
p. 158).

3. Austrian report on the London World Exhibition, 1862, section 14.

4. Phot. News (1861), p. 135.

5. Brit. Journ. of Phot. (November 15, 1862).

6. Of Leahy nothing more was heard, nor do we know who he was.

CHAPTER XLVlll

1. Phot. News (1861), V, 403, and Phot. Notes (1861), VI, 156, ac-
cording to La Lumiere (April 15, 1861 ). Gaudin gave before this sugges-
tions for the production of photogen with collodion and gelatine.

2. La Lumiere (1861), p. 37.

3. Patent No. 1074. Abridgements of Specifications Relating to Photog-
raphy, Part II, p. 26.

4. B. J. Sayce was an amateur photographer, later president of the
Liverpool Amateur Photographic Association. He died 1895 (See obitu-
ary, Brit. Journ. of Phot., 1895, p. 340).

5. W. B. Bolton (b. 1848 in York, d. May, 1899). For his biography
see Brit. Journ. Phot. Alman. (1900), p. 683; his portrait is in Brit. Journ.
of Phot. (May 19, 1899).

6. See Lea’s biography in Brit. Journ. of Phot. (1897), p. 312; Phot.
Mitt., XXXIV, 104. Carey Lea’s photochemical research covers many
fields of photography. Of special scientific interest are his investigations
on red and purple silver chloride, silver bromide and iodide, on helio-
chromy and the latent photographic image; on the allotropic forms of
silver. In 1908 Dr. Liippo-Cramer published, under the title Kolloides
Silber und die Photohaloide von Carey Lea, a German edition of these im-
portant articles which had appeared in the English language in various
periodicals (published by Theodor Steinkopff, in Dresden, with Carey
Lea’s portrait).

7. Brit. Journ. of Phot. (1871), p. 312.

8. In 1908 Stenger reports the frequent use of di-iodofluorescin as
sensitizer for silver bromide collodion halftone negatives ( Handbuch ,
1927, 11(2), 247).

CHAPTER XL1X

1. For Wamerke’s biography see Chapter LXIII.

772

NOTES TO PAGES 381-387

CHAPTER L

1. See Poggendorff, Biograph.-literarisches Handworterbuch. A por-
trait of Wheatstone is in Brit. Journ. Phot. (1868), p. 74. In October,
1925, a bronze portrait plaque of Sir Charles Wheatstone was affixed to
his birthplace in Gloucester, England. He invented, in 1838, the mirror
for the stereoscope (illustrated in Phot. Journ., 1925).

2. I. F. Mascher, Philadelphia, obtained, in 1853, an American patent
on folding stereo-viewing apparatus. It is questionable whether he was
the first to invent it.

3. Brewster, The Stereoscope (London, 1850; German ed., Weimar,
1862). A synopsis of the sources for the history of stereoscopic projec-
tion is published by F. P. Liesegang in Zahlen und Quellen zur Geschich-
r s der Projektionskunst und Kinematographie (1926), p. 106.

4. Paris photographe (1894), p. 24.

5. On the progress of stereoscopy in recent years see Eder, Jahrbiicher
fur Photographie.

6. Stolze, Die Stereoskopie (1908), p. 132.

7. Joseph Charles d’ Almeida (1822-1880) was a professor of physics
in Paris. He founded the Journal de physique and was a charter member
of the Societe de Physique, Paris. His dissertation, “Nouvelle appareil
stereoscopique,” appeared in Compt. rend. (1858).

8. Ernst Mach (b. February 18, 1838, Tucas, Moravia; d. February 19,
1916, Haar, near Munich) was an outstanding physicist and philosopher.
He was professor of physics at the German university in Prague; 1895-
.■901, professor at the university in Vienna. On the occasion of E. Mach’s
death Eder, in the Neues Wiener Tagblatt, February 24, 1916, again
called attention to the fact that Mach was the inventor of Roentgen stere-
oscopy; this fact was mentioned also in German technical periodicals, but
w as disregarded during World War I.

CHAPTER LI

1. C. H. Oakten, who reports on it (Brit. Journ. Phot., 1926, p. 91)
dates the first publication erroneously as 1837; it probably should be
1839 because the sodium thiosulphide did not become generally known
until the publications by Talbot and Daguerre.

2. Heinrich Robert Goeppert (b. 1800, d. 1884) and Gebauer, Breslau,
are reported to have shown microphotographs on daguerreotype plates
with detonating gas on November 29, 1839 (E. Stenger, Geschichte d.
Photo gr., 1938, p. 109).

3. Leon Foucault (1819-1868) was the son of a bookseller in Paris.
This great physicist is widely known through his famous pendulum ex-

NOTES TO PAGES 387-393 773

periment (to demonstrate the rotation of the earth) and through his de-
termination of the speed of light. He made daguerreotypes approximately
from 1843 and, with Donne, constructed an apparatus for microscopic
demonstrations (Compt. rend., 1844).

4. See Recueil des travaux scientifiqucs de Leon de Foucault, by C. M.
Gabriel and Bertrand (Paris, 1878), and Sturmey, Phot. Annual (1898),
p. 176. Foucault, with Donne, described an electrical photomicroscope.

5. J. Gerlach, Die Photo graphie als Hilfsmittel mikroskopischer For-
schung (Liepzig, 1863); Moitessier, La Photographie appliquee aux re-
cherche s micro graphiques (Paris, 1866; German ed., 1868).

6. The Amateur Photographer (April, 1903), p. 349.

7. Physikalische Zeitschrift (1904), p. 666.

8. Following Kohler’s investigations in 1926, C. E. K. Mees suggested
the use of the ultraviolet silver mercury line 365 mm. for microphotog-
raphy. [[Translator’s note: Dr. Mees wrote to the translator “I have no
recollection at all of Kohler’s research in 1926.”] A. P. H. Trivelli and L.
V. Forster investigated this further in the Eastman Kodak Research Lab.
( Journ . Optic. Soc. Amer., February, 1931, Vol. XXI. See also Trivelli,
Kodak Scientific Papers, No. 434, and Phot. Indust. (1931), p. 161.

CHAPTER Lll

1. A. Miethe, for instance, used the old Taupenot silver iodide albumen
process for photomicrography (Zeitschrift f. Instrumentenkunde, 1912,
p. 190); E. Goldberg used Russell’s tannic collodion dry process (Phot.
Indust., 1917, p. 448) and later fine grain silver chloride printing-out
emulsions on glass (Phot. Indust., 1926, p. 379) which require an especi-
ally intensive illumination for the microscope. Eder-Pizzighelli’s silver
chloride gelatine with chemical development were used for photomicrog-
raphy (micrometer scales), owing to their superior fine grain.

CHAPTER Llll

1. Later J. J. Woodward wrote a paper, Heliostat for Photomicrog-
raphy (1869).

CHAPTER LIV

1. On the history of photography from a balloon see Gaston Tissan-
dier, La Photographie en ballon (Paris, 1886).

2. Nadar, “Artiste en daguerreotypie,” as he called himself, had his
studio in Paris, 1 1 3 Rue St. Lazare, in the second half of the past century.
He died in 1910, in Paris, when 90 years old. Nadar published also Petits
albums pour rire, No. 1 (title in woodcut and 224 anecdotal illustrations

774 NOTES TO PAGES 393-401

on 56 pages). Nadar’s son later was a famous portrait photographer in
Paris.

3. Nadar’s British patent is number 2,425 for his balloon photography
and is dated October 29, 1858.

4. John A. Tennant, in his monthly periodical Photo-Miniature (July,
1903, V, 145-173), published an article “Aerial Photography” on the
work of Samuel A. King and J. W. Black with numerous illustrations.
For earlier publications on this subject see A. Batut, La Photographie
aerienne par cerf -volant (Paris, 1890); and H. Meyer-Heine, La Photo-
graphie en ballon (Paris, 1899); also the articles by the Reverend J. M.
Bacon in the periodical Photography (London), April and May, 1893.

,5. See Tissandier, p. 655.

6. See Phot. Archiv (1862), pp. 97, 99; (1863), p. 172; (1864), pp. 134,
409.

7. Phot. Korresp. (1885), p. 388. In Vienna, Allg. Sportzeitung, (Sep-
tember 25, 1885), No. 39, p. 895, as well as in its supplement attached to
November 28, 1886, No. 48, pp. 1-4. V. Silberer, the editor, defends his
priority with regard to the making of the first balloon photograph in
Austria (see N. Wiener Journal, 1900, XXV, 9).

8. La Nature (February 26, 1887).

9. Miethe, Photo gr. Aufnahmen vom Ballon aus. (1917).

CHAPTER LV

1. Laussedat’s portrait in Paris photographe (1892), p. 241.

2. A. Laussedat, Paris photographe (1892), p. 471.

3. Chevalier also constructed in the 50’s an attachment for photograph-
ic measurements of which an example was preserved in the military-
technical collection in Vienna (see Pollack, Mitteilung der k. k. geograph-
ischen Gesellschaft in Wien, 1891, No. 4; see also Eder, Jahrb. f. Phot.,
1897, p. 506).

4. Obituary on Colonel Laussedat, see La Phot. (1907), p. 94, with
portrait; Le Mon. de la phot. (1907), p. 25, as well as Eder, Jahrbuch
(1907), p. 217.

5. See Laussedat, Recherches sur les instruments, les methodes et le
dessin topographiques (Paris, 1903); Laussedat, La Metrophotographie
(Paris, 1899); V. Pollack, “Uber photographische Messkunst” in Mit-
teilungen der k. k. geographischen Gesellschaft in Wien (1891); Paganini,
Fotogrammetrie (Milan, 1901); C. Koppe, Photo grammetrie und inter -
nationale Wolkenmessung (Brunswick, 1896); C. Koppe, Die Photo-
grammetrie oder Bildmesskunst (Weimar, 1889); Meydenbauer, Das
Denkmaler archiv und seine Herstellung durch das Messbildverfahren.
Memoir. (1896); Ed. Dolezal, Die Anvoendung der Photographie in der

NOTES TO PAGES 402 - 408 775

praktischen Messkunst (Halle on the Saale, 1896); Ed. Dolezal, Die Pho-
tographic und Photogrammetrie im Dienste der Denkmalflege und das
Denkm'iierarchiv (Halle on the Saale, 1899).

6. Eder, Jahrbuch f. Phot. (1910), p. 643.

CHAPTER LVl

1. Karl August Steinheil (b. 1801, Rappoldsweiler, Alsace; d. 1870,
Munich) studied astronomy in Gottingen and Konigsberg; he became
professor of physics and mathematics in Munich, 1832; he occupied him-
self with work in telegraphy. In 1849 he entered the service of Austria
as head of the Department for Telegraphy in the Ministry of Commerce,
where he organized the telegraphic system in the Austrian monarchy. In
1851 he did the same in Switzerland, after which he was called as minis-
terial counselor to Munich; in 1854 he founded an optic-astronomical in-
stitution which produced excellent instruments. Karl August Steinheil is
considered to be the scientific founder of electromagnetic telegraphy.
He is said to have made the first daguerreotype in Germany.

2. Ed. Steinheil died 1878 on a trip to South America.

3. Moritz von Rohr, Z ur Geschichte der Zeiss schen Werkstatte bis zum
Tode Abbes, Forschungen z ur Geschichte der Optik, Beilage z ur Z eit-
schrift fur Instrumentenkunde (1930, Vol. I).

4. Dr. Paul Rudolph was a pupil and collaborator of Abbe’s at Jena.
The anastigmatic principle, determined by Rudolph in 1889, acknowl-
edged the importance of high refractoring barium lenses for photo-
optics. During the first years the Zeiss-Rudolph anastigmats found only
a rather unresponsive audience in Germany, whereas in France and
Russia they were received enthusiastically. Rudolph remained with Zeiss,
Jena, until 1910, when he resigned because of poor health. At the out-
break of World War I he was recalled to Zeiss for civilian service and
calculated a strong teleobjective for balloon photographs. Released from
this service, he calculated a new anastigmat, which is described later in
this chapter. P. Rudolph’s biography is to be found in Dr. von Rohr’s
Theorie und Geschichte der photographischen Objektive (1899), dedi-
cated to him. Rudolph gives an account of his later activity in his writ-
ings: Neue Gesichtspunkte fur Anastigmate (lecture delivered in Stutt-
gart on May 12, 1920), “Der Raumzeichner und die Zonenkreise sphar-
ischer Korrektion” (in the periodical Die Kinotechnik, 1929, p. 339) and
in a manuscript, “Dr. Paul Rudolph in eigener Sache,” dated August,
1920. These writings of P. Rudolph are in the library of the Technische
Hochschule, Vienna.

5. These are preserved in the Graphische Lehr- und Versuchsanstalt,
Vienna.

jj6 NOTES TO PAGES 409-414

6. The “plasmat” lenses belong in the group of “anastigmatic sphero-
achromatic objectives” (German patent, No. 420, 223, of 1924 and 1925;
and No. 426, 912, of 1926).

7. A description of Goerz’s career will be found in the Goerz-Festschrift.

8. For a description of these earlier types of Goerz objectives see my
manual Photogr. Objektive ( 1 9 1 1 ) ; the author has placed the originals in
the collection of the Graphische Lehr- und Versuchsanstalt, Vienna.

9. Emil von Hoegh (b. May, 1865, in Lowenberg, Silesia; d. January,
1915) was a descendant of a very old Danish aristocratic family. He had
his first technical education in Karl Bamberg’s precision workshops for
optics and mechanics in Berlin, where the impulse to take up the study
of optical instruments was awakened in him. He applied at the firm Carl
Zeiss, Jena, by offering his cooperation on the basis of his theoretical re-
search which he had carried on privately. He was engaged, but later the
contract was canceled, probably at Bamberg’s instigation. The latter had
informed Zeiss that Hoegh often enough had proved that he did not have
the slightest notion of the simplest mathematical principles. At first
Hoegh was dependent entirely on himself, working in small shops in
Southern Germany, working manually wherever he could find a job (M.
v. Rohr, Theorie und Geschichte des phot. Objektives).

While laboring manually during the day, he continued way into the
night his theoretical studies. He called one day on C. P. Goerz (see
Goerz-Festschrift, the article by W. Zschokke) who at first treated him
coldly; but Hoegh, sketching various forms of lenses on paper, con-
tinued: “I have in mind to calculate a symmetrical objective, in which
the anastigmatic leveling of the image field is accomplished with a light
intensity which at least equals that of lynkeioscopes. ... If you want to
assist me, I promise to submit to you the final calculation of the objective
within a few weeks.” In November, 1892, a model of the first double anas-
tigmat was ready, and a patent for it was filed by Goerz in December
20, 1892, which was granted on May 5, 1893. Hoegh worked with Goerz
until the middle of 1903; because of poor health he moved then to Ros-
tock, later to Goslar (Harz), where he remained until he died. His biog-
raphy may be found in Phot. Korr., 1915, p. 85, and 1916, p. 6; portrait,
same source, 1915, p. 133. Baltin in Phot. Ind., 1930, p. 582, reports on this
ingenious man’s irregular mode of life.

10. For the history of the name “doppel-anastigmat” as applied to the
Goerz objective see Leon Christman (Phot. Indust., 1930, p. 904).

CHAPTER LV1I

1. Lately Chapman (1924) and Kronfeld (1925) confirmed the valid-
ity of the law of reciprocity by Bunsen-Roscoe in mixtures free from

777

NOTES TO PAGES 415 -421

induction (see Eder, “Sensitometrie,” in Handbuch, 1930, Vol. Ill, Part 4).

The mystic nature of the “photochemical induction” kept many photo-
chemists busy. R. Luther and E. Goldberg demonstrated in 1926 that
traces of oxygen retarded the action of light when present in a chlorine
detonating gas mixture. Since the oxygen acts as a negative catalyzer in
photochemical chlorinations, it is only when the oxygen is exhausted that
the photochemical reaction occurs undisturbed. It is thus that the phe-
nomenon of induction is explained (Plotnikow, Allgemeine Photochemie,
1920, p. 94). The many investigations into the photochemical chlorine
detonating gas reaction in reference to the kinetic reaction to the Einstein
equivalence law and to the modern quantum theory, are exhaustively
treated in Nathaniel Thon’s report, “Die Chlorknallgasreaktion” (Fort-
schritte der Chemie, Physik und physikalischen Chemie, 1928, XVIII, No.
1 1; with a foreword by Max Bodenstein).

2. Eder, Handbuch (1884), I, 174 where also similar experiments made
by Jordan, 1839, Hunt, 1845, Herschel, 1840, Claudet, Heeren, 1844,
Schall, 1853, are described. Malagutti published the mentioned study in
Annal. de chim. et phys., LXXII, 5.

3. See Walter Hecht, “Das Graukeil-Photometer im Dienste der Pflan-
zenkultur; eine neue Methode zur kontinuierlichen Messung der Licht-
intensitat,” Sitzungsberichte, Akad. d. Wiss. in Wien, Math-Sc. Class lla
(1918, CXXVII, 2283). Kissling’s merits are there acknowledged and
the more exact methods of photometry of the grayscale-photometer in-
stead of the less exact paperscale photometers are defined.

4. Plotnikow erroneously reports in his Allgemeine Photochemie
(1920), p. 64, that Eder and Valenta, in 1904, had found in a mixture of
oxalic acid -|- mercury silver chloride the photochemical coefficient tem-
perature as 1. 1 9. The error was due to the fact that Eder’s Akademieab-
handlung vom Jahre i8yp was published in Eder-Valenta, Beitriige zur
Photochemie, in 1904, quoting, however, the original source. Because of
the confusion between the years in Plotnikow’s Photochemie, p. 61, E.
Goldberg is mentioned as the first who, in 1902, called attention to these
lowest photochemical coefficient temperatures; Eder’s statement, how-
ever, was made some years earlier.

CHAPTER LV1II

1. Annal. d. Physik u. Chemie (1851), XXIV, 218.

2. See Sale, Proceed, of the Royal Soc., XXI, 283; Poggend., Annal.
CL, 333.

3. Reports of the Berlin Academy, 1875, p. 280; 1876, p. 95.

4. [(The selenium cell is now regarded as out of date and has been re-
placed by various forms of photoelectric cells. Note by William Gamble.]

778 NOTES TO PAGES 422-428

CHAPTER L1X

1. For Dr. R. L. Maddox and the invention of gelatine-emulsion plates
see also Photography ( 1901 ), p. 56 and portrait; W. Jerome Harrison, A
History of Photography (Bradford, 1888); Brit. Journ. of Phot. (1901),
p. 425; Richard Jahr in Handbuch (1930), Vol. Ill, Part 1, ch. 1.

2. Maddox’s fellowcountrymen also shared the opinion that it was he
who invented the silver bromide gelatine plate. The president of the Royal
Photographic Society of Great Britain proposed at the meeting of August
1, 1901, that the Progress Medal be awarded to Dr. R. L. Maddox as “the
inventor of the gelatine silver bromide dry plates, causing a revolution in
photography and its application,” which was accepted unanimously. This
distinction, bestowed upon Dr. Maddox as the inventor of the silver-
bromide gelatine plate, is all the more important since it was awarded to
him by British experts, his contemporaries, who were the best judges of
the conditions. I should like to point this out to those who have doubts as
to Maddox’s share in this invention.

3. See Maddox’s complete biography in Brit. Journ. Phot. (1902), pp.
425, 427; and obituary, Brit. Almanac (1903).

4. Photo graphisches Archiv (1881), XXII, 120.

5. The founder of the firm Wratten & Wainwright was F. C. L. Wrat-
ten; he died April 8, 1926, in London at the age of 86.

6. Bull. Soc. franp. d. phot. (1879), p. 204; also Phot. Korresp. (1879),
XVI, 149.

7. According to W. Ostwald’s later theory of ripening, the larger silver
bromide particles increase at the expense of the smaller ones which are
more soluble (see Liippo-Cramer in Handbuch, 1930, III ( 1 ) , 47). For W.
Ostwald’s theory of the chemical development of the latent image see
his Lehrbuch der allgemeinen Chemie (1893), II, 1078; also Eder, Hand-
buch (1903), III, 871.

8. The hypothesis as to the formation of three silver bromide modifi-
cations to which J. S. Stas referred in his determination of atomatic
weight and which Monckhoven used for the explanation of the “ripening
process” are not sufficient. J. M. Eder was the first to point this out, in
June, 1881 (Phot. Arch., 1881, p. 109); he was of the opinion that in the
process of ripening silver bromide gelatine the silver bromide was reduced
very little and that these traces of silver are involved with the increase of
the sensitivity. Thus the silver bromide of the ripe emulsion must contain
a minimal surplus of silver. Weigert and F. Liihr, as well as H. H.
Schmidt and F. Pretschner, confirmed this much later by chemical quan-
titative analysis (see Eder, “Das Reifen der Bromsilbergelatine,” Zeit. f.
ivissensch. Phot., 1930). The later theory of electronics also adopts Eder’s
opinion of the development of free silver during the ripening of the silver

NOTES TO PAGES 431 -432 779

bromide gelatine; S. E. Sheppard at the 8th International Congress for
Photography, Dresden, 1931 (see Phot. Indust., 1931, p. 905), reported
on this. See Handbuch (1927), II ( 1 ), 9.

9. In 1883 Carl Haack, Vienna, sold a dozen dry plates, size 19 x 12 cm.
for 1 gulden 30 kreuzer, plates size 18 x 24 cm. for 4 gulden 80; silver
bromide gelatine in the shape of noodles, preserved in alcohol, for 14
gulden per kilogram.

10. Director Simeons moved later to London, where the gelatine fac-
tory “Simeons” still exists to this day. The factory in Winterthur contin-
ued to produce its own kind of gelatine.

11. Carl Haack (b. 1842, Schwerin; d. 1908) came to Vienna in 1865.
As chemist he devoted himself to photography, especially to reproduc-
tion photography, and worked in his own studio for the photoengravers
Angerer and Goschl (Vienna III, Landstrasse, Hauptstrasse) until they
opened their own studio. In 1888 he sold his dry-plate factory, started in
1879, in which he had first introduced the fulminating silver method, in
1881, to Engelhardt and Schattera (later Langer & Co.). He then moved
to Dresden, where he painted landscapes. Biography and portrait are in
Phot. Korresp. (1909), p. 585.

12. Professor Ferd. Hrdlicka and Professor Alexander Lainer were
teachers at the Graphische Lehr- und Versuchsanstalt, to which they had
been called by Director Eder. Engineer-chemist Ferdinand Hrdlicka (b.
i860), the son of an estate-manager in Moravia, attended the German
Staatsrealschule in Brlinn, graduated from the chemical training school of
the Technische Hochschule, in Vienna, in 1882. He worked for one year
as chemist in a sugar refinery. After this he worked with the inventor of
the collotype process, Professor Husnik, in Prague, studying various
techniques of reproduction; in 1884 he started a photoengraving estab-
lishment in Vienna, where he produced collotypes and zinc etchings. In
1889 he was called as teacher to the Graphische Lehr- und Versuchsan-
stalt; in 1893 he resigned, however, to start a factory in Vienna for the
production of photographic paper, where he also introduced (1895) his
invention of “Rembrandt-celloidin-papers”; his business grew and pro-
duced finally all kinds of photographic paper commonly used in the trade,
as well as all sorts of photographic plates. He is still active today after
having combined with the photographic works of Professor Alex. Lainer
as partner in the firm Lainer & Hrdlicka.

13. The factory for dry plates and films, Hauff, in Feuerbach, near
Stuttgart, developed from the chemical works which Julius Hauff es-
tablished in 1870 for the production of fatty preparations; he produced
there pure phenol, salicylic, and picric acid for the armed forces (1888),
etc. After his death his son. Dr. Fritz Hauff, produced, among other

780 NOTES TO PAGES 433-439

items, also by-products for the coal-tar industry and photographic prepa-
rations. As early as 1890 they attempted the production of dry plates. At
that time more stress was laid on the production of developer prepara-
tions. Dr. A. Bogisch, the chemist with the firm of Hauff, was extremely
successful in this field (metol, amidol, glycin, ortol, etc.). In the early
years of the 20th century the production of dry plates and films on a
large scale was taken up in Feuerbach.

14. Berkeley, Phot. News. (1882), p. 41; Phot. Korresp. (1882), p. 47.

15. Berkeley, Phot. News (1882), p. 41; he also drew attention to the
use of acidulous alum baths as agents for the prevention of yellow fog
on negatives (Brit. Journ. Phot., 1881, p. 59).

16. Carey Lea, Brit. Journ. Phot. (1877), pp. 192, 304; also Phot. Ar-
chiv (1877).

17. Carey Lea, Brit. Journ. Phot. (1880); Phot. Archiv (1880), p. 104.

18. Phot. Korresp. (1879), p. 223. In a letter of May 7, 1880, to the
Brit. Journ. Phot. Carey Lea admits that F.der’s mixture of ferro-vitriol
and potassium oxalate is preferable to other, more complicated ferro de-
velopers.

19. According to a statement of L. Tennant Woods (Brit. Journ. Phot.,
1927), Dr. Baekeland is supposed to have been the first to introduce the
metal-hydroquinone developer for developing positive paper images (for
“the velox paper invented by him” in 1893). This statement must be
closely examined, because historical data quoted from this source are
questionable. The “invention” of the velox paper is also erroneously cred-
ited to the same Mr. Baekeland by these sources. This does not differ
from the invention of Eder and Pizzighelli of silver chloride gelatine with
chemical development. When the Eastman Co., in 1 899, took over Baeke-
land’s plant, they also continued the metal-hydroquinone developer as
standard for their silver bromide gelatine films.

20. It was first Carey Lea (in his article “Comparative Influence of
Soluble Chlorides, Bromides and Iodides on Development,” Brit. Journ.
Phot., 1880, p. 304) and Dr. Szekely, of Vienna, in Phot. Korresp. (1882),
p. 57 (Eisenoxalat-entwickler), who in their experiments added potas-
sium iodide to the ammonia pyrogallic developer for the purpose of re-
tarding development without, however, achieving the so-called “Lainer
effect.”

21. The basic invention which made the bromoil print possible also
originated from E. Howard Farmer’s research.

CHAPTER LX

1. S. E. Sheppard of the Eastman Kodak Research Institute in Roches-
ter published such a diagram in the Journal of Chemical Education, 1927,
Nos. 3-6.

NOTES TO PAGES 439-445 781

2. For further progress of photography into the ultraviolet see Guthrie
lecture, Society of Physics, by Professor M. Siegbahn, Studies in the Ex-
treme Ultra Violet and the Very Soft X-Ray Region (1933).

3. “The Infra-red Content of Daylight,” G. B. Harrison, Ph.D., and
“Development in Infra-red Photography,” Olaf Block, F.I.C., Phot. Jour-
nal (August, 1932, and April, 1933).

4. “Recent Advances in Sensitizers for the Photography of the Infra-
red,” by Brooker, Hamer, and Mees in Abridged Scientific Publications
from the Kodak Research Laboratories, 1933-1934 (XVI, 75, Communi-
cation No. 513).

5. Taken from “Fifty Years of Photography,” by C. E. K. Mees, print-
ed in Industrial and Engineering Chemistry (1926), XVIII, 916.

CHAPTER LXI

1. A biography, Sir J. W. Swan, a Memoir, by Mary Edmonds Swan
and K. R. Swan, is published by Ernest Benn, 1929.

2. Phot. Korresp. (1883), p. 332; (1884), p. 330. German patent (D.R.
P.) No. 26,620, April 15, 1883. Schlotterhoss exhibited his automaton for
copying in the Electrical Exhibition, 1883, in the Rotunde, Vienna.

3. The chemist Dr. E. Just was the first manufacturer of silver bromide
and chloride gelatine in Vienna. About 1880-83 produced only albumen
paper, which at that time was the predominantly used copying-out paper.
In 1883 he took up the production of gelatine emulsion developing paper.

4. The first automaton for copying used by the Neue Photographische
Gesellschaft, Berlin, is illustrated in Eder’s Jahrbuch (1896), p. 479.

CHAPTER LX11

1. In Ludwig Darmstaedter’s Handbuch zur Geschichte der Natur-
wissenschaften und der Technik (2d ed., Berlin, 1908, Julius Springer, p.
791 ) appears the following note: “1881, Eder and Pizzighelli discover the
silver chloride gelatine paper as positive paper and the silver chloride
gelatine emulsion process at which the image appears completely in the
emulsion during the exposure, so that it need no longer be developed fur-
ther, but needs to be only toned and fixed.” This statement is erroneous.
Eder’s and Pizzighelli’s silver chloride gelatine process concerns itself
with the bringing forth of the latent light-image by means of chemcial
developers, while on the other hand the silver bromide gelatine copying-
out paper has been invented by Abney.

2. F. Stolze, who later in his small factory manufactured commercially
silver bromide and silver chloride gelatine paper (the latter after Eder’s
and Pizzighelli’s publication) introduced as a variation of the toning with
gold the mixed gold fixing bath for toning such photographs, a process

782 NOTES TO PAGES 450-453

which had been previously applied for collodion and aristo papers; it was
a composition of sodium thiosulphate, alum, table salt, ammonium, sulpho-
thiocyanate and some chloride of gold (Phot. W ochenbl., 1887, p. 54).

CHAPTER LXI1I

1. See Eder, “Sensitometrie,” in Handbuch (1930), Vol. Ill, Part 4.

2. Josef Plener convinced this author that Wamerke was a Russian by
birth. Plener was a Pole in czarist Russia and at that time involved in a
Polish revolt against Russia. He fled to London as a Russian emigrant. He
devoted himself to photography and invented his centrifugal machine for
using silver bromide in the production of gelatine emulsions. In 1882 he
came to Vienna to work in Eder’s laboratory. Later he started the dry-
plate factory Lowy-Plener, in Vienna, the firm which first manufactured
Eder’s orthochromatic erythrosin plates. In London, Plener had close per-
sonal contact with Wamerke, with whom he was able to converse in
Russian, his mother tongue, and he always described Wamerke as a Rus-
sian.

3. Scheiner’s complete biography is found in Vierteljahresschrift der
Astronomischen Gesellscbaft, 1914, Vol. XLIX.

4. Dr. Franz Stolze, son of Wilhelm Stolze (b. 1798, d. 1867), who
was founder of a German shorthand system named for him. Dr. F. Stolze
was a physicist and a chemist, and he turned successfully to photography
about 1880. As early as around 1870 we find his articles in technical
periodicals, mostly dealing with the collodion process. He joined an ar-
chaeological expedition to the ruins of Persepolis (equipped by the Prus-
sian State) as a photographer; he used on this occasion silver bromide
collodion plates with an alkaline solution of carmine sulphuric acid and a
gum-sugar preservative. He achieved magnificent negatives (Phot. Wo-
chenbl., 1881, p. 245). He suggested the backing of the plates with auri-
collodion to keep the images free from halo (1882); he started and ran a
small factory for photographic paper in Berlin; he introduced the use of
potash in pyrodeveloper for silver bromide gelatine plates; he found a
method of photographic determination of location without a timepiece
and the junction of the intersecting points (1893). He started the Photo-
graphisches Wocbenblatt, a well-known periodical (1882-89), an d the
Photo gr aphis cher Notiz-Kalender (1896), etc.; he wrote monographs on
apparatus for panorama, enlargements, stereoscopes, etc. (W. Knapp,
Halle). Of special importance are his experiments and publications on the
determination of the sensitivity and graduation of photographic plates,
reported in Handbuch (1930), Vol. Ill (4), “Sensitometrie.” By profession
Stolze was a teacher of shorthand at the University of Berlin and had the
title professor.

NOTES TO PAGES 453-459 783

5. Literature on the gray scale: Dr. E. Goldberg, “Die Herstellung
neutral grauer Keile und veraufender Filter fur Photometrie und Photo-
graphic” ( Jahrb ., 1911, p. 149; see also Z eitschr. f. wissensch. Phot., 1912,
p. 238; Phot. Korresp., 1917, p. 82); A. Hiibl, “Die Bestimmung der
farbenempfindlichen photographischen Platten,” Phot. Korresp. (1918),
P- 379; ( I 9 I 9>» P- 363-

6. The controversy between Eder and Goldberg (Phot. Ind., 1927,
Nos. 11, 18; also Eder’s “Sensitometrie,” Handbuch, 1930, III (4), 396) de-
termined Stolze’s priority in the use of the gray scale in sensitometry.

7. Experiments by Janssen, Abney, and others are described in great
detail in Eder’s “Sensitometrie,” Handbuch (1930), III (4), 174.

8. Dr. Kron’s family left Potsdam after his death, and later inquiries
remained fruitless.

CHAPTER LXIV

1. See Phot. Korresp. (1899), p. 68.

2. Schiendl, Geschichte der Photographie, described the invention of
the color-sensitive process quite incorrectly. Owing to some sharp,
though justified, criticisms on the part of H. W. Vogel (Phot. Mitt.),
Schiendl became his personal antagonist. L. Schrank, of Vienna, his coun-
selor, also had personal differences with Professor Vogel, a temperamen-
tal person who wrote the truth with a virulent, though justified, pen.
This caused Schiendl to lose his clear and objective judgment of the situa-
tion. He states in his Geschichte (p. 169) that H. W. Vogel published in
May, 1884, his (Vogel’s) color-sensitive collodion process “on the basis
of investigation published by Schultz-Sellack in 1871.” Schiendl cites
there the Berichte der deutschen chemischen Gesellschaft (1871) and
Pogg. Annal. (1871). Strange to say, the source to which the author re-
fers does not contain one single word justifying his denial of Vogel’s in-
dependent discovery. If one studies the source to which Schiendl refers,
one will find an article by Schultz-Sellack on the reaction of silver iodide,
and so forth, to the spectrum; but this has no bearing whatever on Vo-
gel’s famous discovery of color-sensitive photography. H. W. Vogel in-
creased the color-sensitivity— always keeping in mind the result which he
wished to obtain— by adding dyestuffs to silver bromide. Schultz-Sellack
used the old process of iodide-bromide and iodide-chloride collodion
without the least addition of a sensitizing color substance. It is this which
makes it quite useless for correct orthochromatic photography, while Vo-
gel’s discovery initiated a complete reversal in the photographic repro-
duction of colored objects. H. W. Vogel and Eder have corrected
Schiendl’s statement in Phot. Korresp. (1891), p. 154, and Phot. Mitt.,
XXVII, 243, 325.

784 NOTES TO PAGES 459-463

3. H. W. Vogel, Ber. d. deutsch, chem. Ges. (1873), VI, 1305, and
(1875), 1635; Phot. Mitt., IX, 236.

4. Brit. Journ. of Phot. (March, 1874); Phot. Mitt., XI, 27, 97.

5. Azaline plates were hardly suitable for portrait photographs, because
the cyanine reduced the entire sensitivity considerably.

6. H. W. Vogel was occupied in 1884 also with eosin plates, and by
adding “eosin silver” to the silver bromide emulsion he produced ortho-
cliromatic plates which showed good color sensitization together with a
greater general sensitivity. For the exploitation of this matter he sought
collaboration with the Munich photo-technician J. B. Obemetter, who
introduced the plates on the market as “Obernetter-Vogel-eosin-silver
plates.” After Obemetter’s death, on March 12, 1887, Vogel was con-
nected with the dry-plate factory of Otto Perutz. It may be mentioned
here briefly that the early Obernetter-Vogel-eosin-silver plates proved
perishable, due to the predominance of silver salt, which led to complaints.
They avoided this objection later by limiting themselves in neutralizing
the disturbing excessive potassium bromide, which was characteristic of
the washed emulsion, by adding silver nitrate or eosin silver.

7. The author, who was connected with Dr. Vogel in constant scien-
tific and personal relations, possessed a broad basis for a historical record
of his life and career. In addition to this Professor E. Stenger, one of Vo-
gel’s successors at the Berlin Technische Hochschule, sent the author fur-
ther interesting data and also a portrait of young Vogel (1865). Stenger
also enriched the biographical material very appreciably.

8. H. W. Vogel, Die Photographic auf der Londoner Weltausstellung
1862 (Brunswick, 1863); also in Bollmann, Photogr. Monatshefte (1862),
Nos. 6-9.

9. Vogel, Praktische Spektralanalyse irdischer Stoffe, was published in
1877, and a second edition in 1889.

10. The seemingly common use of photographs on cards of identifica-
tion, passports, etc., probably was due to a suggestion of H. W. Vogel,
who initiated them on the admission tickets to the Berliner photographi-
sche Ausstellung, in 1865, which was a matter for ridicule in the Brit.
Journ. Phot. (1865), p. 227.

11. Two books, Vom indischen Ozean bis zum Goldlande (Berlin,
1877), and Lichtbilder nach der Natur (Berlin, 1879), contain popular-
scientific descriptions of his travels anil of his research work.

12. Everywhere Vogel found recognition, even abroad; notwithstand-
ing this, France calls him in a special issue of the Figaro Photographe
(1892), on the occasion of a photographic exhibition on the Champ-de-
Mars, in four places the “Autrichien,” and the “Viennois,” respectively;
and in addition a portrait appears there of a bearded man who is not Vo-
gel at all! (Stenger)

NOTES TO PAGES 463 -471 785

13. First in serials 1867-70; then in the 2d ed., 1874; 3d ed., 1878; 4th
cd., in several volumes, 1890-99; only under his name, but completely re-
vised, the work was published, 1925-28, in Berlin (ed. by E. Lehmann);
Ernst Konig had already issued in 1906 a 5th ed. of the volume Photo-
chemie und photo gr aphis che Chemikalien. Anyone who wants to know
H. W. Vogel more thoroughly needs to read the earlier original editions.

14. Phot. Mitt, 1868, IV, 293, 320.

15. See autobiography in Brockhaus, Konversationslexikon (13th ed.,
1887), p. 305, where he is said to have edited all technical terms in pho-
tography; also Photogr. Rundschau (1895), IX, 62.

16. For necrology on Vogel and his portrait see Phot. Mitt., 1901,
XXXVIII, 279.

17. Also published in Phot. Archiv (1878), p. 109.

18. Compt. Tend., LXXXVIII, No. 3, p. ii9;No. 8, p. 378 \Phot. Korresp.
(1879), p. 107.

19. Ducos du Hauron does not seem to have appreciated the import-
ance of the orthochromatic process (for instance, the eosin collodions)
for true color values of monochrome reproductions, but had always in
mind only its application to the three-color process.

20. See Eder and Valenta, Beitrdge z ur Photochemie und Spektralana-
iyse (Vienna and Halle a. S., 1904), III, 13 1; Phot. Korresp. (1899),
p. 336.

21. See Eder. Phot. Korresp. (1904), p. 215.

22. Eder defended his claims to priority for the discovery of erythro-
sin as a sensitizer in a controversy directed against Mallmann and Scolik;
see his “Zur Geschichte der orthochromatischen Photographic mit Eryth-
rosin,” Phot. Korresp. 1890), p. 455; also Eder and Valenta, Beitriige zur
Photochemie und Spektralanalyse (1904), III, 78.

23. Sitzungsberichte d. kais. Akad. d. Wiss. (Vienna, 1884), XC, 1097.

24. Eder’s original study was published under the title “Uber das Ver-
halten der Haloid- Verbindungen des Silbers gegen das Sonnenspektrum
i:nd die Steigerung ihrer Empfindlichkeit durch Farbstoffe,” Sitzungsbe-
richte d. kais. Akad. d. Wiss. (Vienna, December 4, 1884); printed in
Eder and Valenta, Beitrdge zur Photochemie und Spektralanalyse (1904).

25. In the periodical Gr aphis che Kiinste (Vienna, 1885), Eder pub-
lished a profusely illustrated study on the use of erythrosin plates for
the reproduction of paintings. The reproduction on p. 653 of the German
edition is made from an orthochromatic negative on erythrosin-cyanide
plates and shows a preponderance of red.

26. Valenta’s red color sensitization of silver bromide collodion with
ethyl violet was introduced in all classes at the Graphische Lehr- und
Versuchsanstalt, Vienna (1898). Guido Raubal, who studied there in

786 NOTES TO PAGES 475-489

1898-99, learned of it. When he was employed by the British factory mak-
ing silver bromide collodion he brought with him the ethyl violet which
had been given to him. It had been unknown there as a sensitizer up to
this time, and it was he who introduced it successfully into manufacture.
At the outbreak of the World War Raubal returned to Austria; he fell in
Galicia. Paul Szulmann, assistant at the Graphische Lehr- und Versuchs-
anstalt (b. January 25, 1887, in Budapest) introduced ethyl violet in
France, in the engraving establishment of Louis Geissler, Paris; he used
ethyl violet in combination with Albert’s silver bromide collodion; Szul-
mann went later to Belgium; he served in the World War as an officer in
the reserve, and in 1919 took a position with Ullmann in Berlin; later with
W. Biixenstein in Berlin.

27. This memorial tablet was removed after his death.

28. Pope took this product erroneously for Hochster pinachrom,
which contains two ethoxy groups. The constitution of the British dye-
stuff is 6'-methoxy-6-ethoxy-i-i'-diethylisocyanineiodide; that of the
Hochster product, 6'-ethoxy-6-ethoxy-i-i'-diethylisocyanineiodide (bro-
mide).

29. Onrubrocyanine see Eder, “Sensitometrie,” Handbuch ( 1930, III (4),
242), and Dieterle, in Handbuch (1932, Vol. Ill, Part 3).

CHAPTER LXV

1. Luppo-Cramer defends his claims to priority against Lumiere and
Seyewetz in his book, “Die Grundlagen der photographischen Negativ-
verfahren,” in Handbuch (1927, II ( 1 ) , 678).

CHAPTER LXVI

1. The term “film” originates in the Anglo-Saxon word “filmen,” i.e.,
the scum wliich forms on boiled milk.

2. Handbuch (1927), Vol. 11(3).

3. John W. Hyatt, the inventor of celluloid (see Eder, Jahrbuch, 1915-
20, p. 21), died, 82 years old in June, 1920, at Newark.

4. Eastman’s biography and the growth of the Eastman Kodak Com-
pany is exhaustively described in the work, George Eastman, by Carl W.
Ackerman (1930); also, “George Eastman und sein Lebenswerk,” by Dr.
Fritz Wentzel, of Binghamton, N. Y., in Phot. Korresp. (1927), pp. 161-
67, and various articles in photographic almanacs and periodicals. (See also
Epstean in Photo-Engravers Bull. Sept. 1935, pp. 10-27).

5. See Photogr. News (1888), p. 578; also described in detail in Eder,
Handbuch (1892), 1(2), 545, illus. 71 1. The manipulation of this hand cam-
era with the fixed focus and good, inexpensive objectives, with two
symmetrical lenses like the Steinheil periscopes, the focal difference which

NOTES TO PAGES 490-496 787

is calculated in the permanent focal fixation, was simple, and the develop-
ing and loading of the camera was done by Eastman Dry Plate and Film
Company, which was then the official name. At that time was coined the
slogan, “You press the button, we do the rest,” which was painted in big
letters on the face of the Eastman Company building and which every
dealer in photographic materials appropriated for his own.

6. Everybody's Magazine (New York, June, 1926), p. 24; F. Wenieel,
Phot. Korresp. (1927), p. 16 1.

7. Eder Jahrb. f. Phot. (1903), p. 475.

8. Phot. Archiv (1893), p. 522; Phot. News (1894), p. 469; Phot. Wo-
chenbl. (1901), p 312; Deutsche Phot. Ztg. (1901), p. 849.

CHAPTER LX VII

1. Sacher, Phot. Korresp. (1897), p. 1; F. Paul Liesegang, Kinotech-
nik ( 1919), No. 4.

2. J. Plateau, “The Inventor of the Stroboscope,” in Bull, de I'Academie
royale de belgique, 1883, 3d ser., Vol. VI, Nos. 9-10.

3. A complete description of Plateau’s disk, together with a sample
table, is found in the Gottingen University Library, Section Phys. Math.,
II, 3620. The illustration of Plateau’s stroboscope shows a diameter of 24
cm. F. Paul Liesegang, to whom we are indebted for the most detailed
history of the invention of the stroboscope (see Die Kinotechnik , 1924,
Nos. 19-20), illustrates the first table of Plateau with the stroboscope disk.

4. See Biography by J. Herr, “Simon Stampfer, eine Lebensskizze,” in
Almanack der Kaiserlichen Akademie der Wissenschaften (Vienna, 1865),
XV, 189-216. On pages 212-16 we find Stampfer’s various writings listed.
The passage on the stroboscopic disks reads: “In passing we mention only
. . . his stroboscopic disks, which made his name known everywhere.”

5. “fiber die optischen Tauschungs-Phanomene, welche durch die stro-
boskopischen Scheiben hervorgebracht werden” in Jahrbiicher des k. Poly-
technischen Institutes in Wien (1834), XVIII, 237-58. The insert issued
with the 2d ed. of the tables is entitled: Die stroboskopischen Scheiben;
oder, Optischen Zauberscheiben, deren Theorie und wissenschaftliche
Anwendung, erklart von dem Erfinder S. Stampfer.

6. Stampfer’s description of his Austrian patent for the stroboscope, in
which the first attempts at cinematography are based, reads as follows:
“Application for a two-year privilege of Simon Stampfer, professor at the
k. k. Polytechnisches Intitut, and of Mathias Trentsensky, borh of Vienna,
on the invention of the stroboscopic disks. Granted May 7, 1833; expired
1835. The principle on which this device is based is that any act of vision
which creates a conception of the image seen is divided into a suitable
number of single moments; these present themselves to the eye in rapid

788 NOTES TO PAGES 497 - 506

succession, so that the ray of light falling on the change of the images is
interrupted, and the eye receives only a momentary visual impression of
each separate image when it is in the proper position. The easiest way is
to draw these images on cardboard or any other suitable material on the
periphery of which are pierced a sufficient number of openings for view-
ing-depending on the number and the speed of the images. Revolving
these disks on their axes rapidly in front of a mirror the animated images
are seen in the mirror through the openings.” (For a description of the
invention and improvements for which the Austrian patent was granted
see the official patent office publications Vol. 1, covering 1821-35 (Vienna,
Government Printing Office, 1841).

7. See O. Volkmer, Wiener phot. Blatter (1897), P- 9 2 ; Sacher, “Zur
Geschichte der objekdven Darstellung von Reihenbildern,” Phot. Korr.
(1897), p. 1.

8. For an illustration of both apparatus see F. Paul Liesegang, “Ucha-
tius und das Projektions-Lebensrad” in Kinotechnik (1920), Vol. II, Nos.
7-8.

9. SeeF. Paul Liesegang, Kinotechnik (1921), No. 1.

10. Eder, Jahrbuch f. Phot. (1912), p. 288; Wilhelm Dost, Geschichte
der Kinematographie (1925), p. 13.

11. The motion picture periodical, Le Cineopse (1924), p. 449.

CHAPTER LXVIll

1. For Muybridge’s biography see Sir Sidney Lee, Dictionary of Nat-
ional Biography (London, 1912), 2d Suppl., II, 668-69; Konrad Wolter,
Filmtechnik (1928), IV, 239, 258, 281; Wolter and Seeber, Filmtechnik,
special issue on the occasion of the Leipzig Spring Fair (1930), p. 1.

2. Marey’s report, La Chronophotographie (Paris, 1899), p. 6.

3. K. Wolter and Guido Seeber, “Zwei Hundertjahrige,” in Filmtech-
nik (1930), Vol. VI, Part 5, p. 2.

4. K. Wolter describes Muybridge’s technique of exposure in Pennsyl-
vania precisely in Filmtechnik (1928), IV, 258.

5. A copy of this work is in the library of the Hohere Staatsgewerbe-
schule, Vienna I, now called Technischgewerbliche Bundeslehranstalt. A
new edition, illustrated with halftones, appeared under the title, Animals
in Motion, London, 1899, a copy of which is in the library of the Graph-
ische Lehr- und Versuchsanstalt, Vienna.

CHAPTER LXIX

1. Janssen was an astrophysicist and director of the Astrophysical Ob-
servatory, Paris; he discovered the possibility of observing the protuber-
ances on the sun even when there was no solar eclipse; he had an obser-

NOTES TO PAGES 506-515 789

vatory established on Mont Blanc for investigating the influence of the at-
mosphere on the solar spectrum reaching the earth. His bust was unveiled
in Meudon, October 31, 1920.

2. W. Campbell constructed an incomplete “photographic pistol” with
a rotary plate in 1861.

3. The conference was presided over by Admiral Mouchez, at the time
director of the Paris observatory. The Austrian government was repre-
sented by Professor Dr. E. Weiss, director of the university observatory,
Vienna, the German by Professor Dr. H. C. Vogel and Dr. O. Lohse,
Potsdam.

4. On Marey see Die Filmtechnik, 1930, special issue for the spring
fair in Leipzig; also obituary by R. du Bois-Reymond, Naturw. Rund-
schau, XIX, 904.

5. Marey wrote a number of works on motion: Physiology medicale
et la circulation du sang; Du mouvement dans les fonctions de la vie;
La Machine animale locomotion terrestre et airienne; Developpement
de la methode graphique par la photographie (Paris, 1884); Le Vol des
oiseaux; La Locomotion et la photographie (Paris, 1886); Le Mouvement
(Paris, 1894); La Chronophotographie (Paris, 1899); Fonctions et or-
ganes (Paris, 1902).

6. From a pamphlet distributed in Paris in 1926; published by Eder in
Kinotechnik, 1926.

CHAPTER LXX

1. Ottomar Anschutz’s biography (d. May 28, 1907, Berlin), written
by his son in Umschau (1927), p. 483.

2. Anschutz took also photographs of military maneuvers; on Krupp’s
shooting range at Meppen near Essen he tried to take photographs of pro-
jectiles. The shutter was closed over the plate through its own weight
(exposure one-millionth of a second). The shutter was released electrical-
ly by the shell itself, which broke the current connected with the camera.

3. Eder, Jahrbuchf. Phot. (1888), p. 176; (1891), p. 35.

4. See Eder’s Handbuch (1893), 1(2), 592.

CHAPTER LXXI

1. For further information see F. Paul Liesegang, Phot. Ind. (1915), p.
330; Zahlen und Quellen zur Geschichte der Projektionskunst und Kine-
matogr. (Diisseldorf, 1926), p. 67.

2. Henry V. Hopwood, in his book Living Pictures (1889).

3. The French motion picture periodical Le Cineopse opposes strongly
a committee of the Societe Franf. de Phot, assembled March 31, 1924,
which consisted, not of practical experts in motion picture photography,

79° NOTES TO PAGES 515-522

but of physicians, etc., who unjustly intended to attribute to the physi-
cian Marey the priority in the invention, which was not due to him.

4. Friese-Greene (b. 1855 in Bristol, d. May 5, 192 1, as he was about to
address a meeting) devoted himself with great skill to the field of stereo-
scopic and color motion picture photography (see Brit. Journ. of Phot.,
1921, p. 281). He had an extraordinary talent for invention and excep-
tional dexterity in mechanics, although he was unable to surmount even
the elements of chemistry and physics. Effective as he was as an inventor,
he died in poverty, having sacrificed most of his money on the invention
of printing electrically without inks (Phot. Korr., 1921, p. 208).

5. C. W. Ackerman, George Eastman (1930).

6. The synchronized combination of film with the gramophone, at-
tempted by Edison, could not be made practical for the cinema industry
until the electrical sound transmission was possible through the invention
of the “amplified tubes.” This invention is to be credited mainly to Philipp
von Lieben, of Vienna, and his collaborators Reiss and Siegmund Strauss,
who, independently of but simultaneously with the American Lee de Forest,
had in 1910 constructed the first tubes of this kind. This step opened the
way to the sound film.

7. The detailed description of construction of Edison’s kinetoscope is
to be found in Eder, Jahrb. f. Phot. (1896), p. 389.

8. The term “cinematographe” was used by Bouly in a French patent
application as early as February 12, 1892. From this term the abbrevia-
tion “cinema” was derived.

9. See Phot. Korresp. (1896), p. 217. Lumiere’s first patent was later
followed by supplementary patents.

10. Max Skladanowsky showed on November 1, 1895, in the Berlin
Wintergarten filmstrips, which he had taken with an apparatus invented
by him. These “bioscope” performances were presented as rather unim-
portant interludes between two numbers in a variety show. These pro-
jected motion pictures were primitive; they showed dancers, acrobats, and
the like. The filmstrips were very short; it did not take longer than six
seconds to show one of them. This was why they were glued together in
rolls and projected successively without interruption in the same way as
were picture strips in the earlier marvel drum. The positives of the film
strips were perforated at the margin, and metal eyelets were inserted. The
projected images flickered considerably. Skladanowsky produced only
eight images per second. Two projection apparatus, which contained the
same film rolls and worked simultaneously, were used for each projection.
During intervals of darkness in one apparatus, the other was kept project-
ing to fill the pause. There were always two identical images projected on
the screen in order to achieve a frequency of sixteen images per second.

NOTES TO PAGES 522-534 791

Skladanowsky had this projection apparatuss patented, D.R.P. No. 88,599,
November 1, 1895. The Skladanowsky brothers intended to show this
method in Paris in spite of its imperfections. They arrived in Paris at the
end of December, 1895, and made a contract with the Folies Bcrgeres ac-
cording to which the “biograph” should be put on the program for Janu-
ary, 1896. But there the Lumiere brothers got ahead of them with a per-
formance of their “cinematographe” which was by far superior to that of
the Skladanowsky brothers. While the Folies Bergeres paid the Sklada-
nowsky brothers the stipulated fee, they canceled the show. (“Diskussion
um Skladanowsky,” by Guido Seeber and Konrad Wolter, in Filmtech-
nik, 1931, VII, 1).

11. K. Albert, Neues Wiener Tageblatt (July 19, 1924); Beranek, in
Filmtechnik (1925), p. 296, with illustrations of Reich’s apparatus.

1 2. Ludwig Mach, Ernst Mach’s son, carried through in practice the
cinematographic time lapse photography of plant growth (Phot. Rund-
schau, 1893, p. 12 1).

CHAPTER LXX11

1. Ernst Mach, Phot. Korresp. (1884), p. 282; E. Mach, “Beitrag zur
Mechanik der Explosionen” ( Sitzber . d. Akad. Wiss. Vienna, July,
1885); E. Mach, Die spektrale und stroboskopische Unterscheidung td-
nender Korper (Prague, Calve, 1873); Eder, Jahrbuch (1888), p. 286.

CHAPTER LXXI11

1. Edinburgh Journ. of Science (1826), p. 319.

2. Handbuch (1912), 1(3), 432.

3 . On Van der W eyde see Handbuch (1912), 1(3), 439, where also Lie-
bert’s night studio is described.

4. The first establishment equipped for the extensive commercial pro-
duction of enlarged photographs on linen was started by M. L. Winter
(1824-99) in Vienna in 1877.

5. Phot. News (1865), p. 550; Phot. Wochenbl. (1883), p. 79.

6. See P. Baltin’s memoirs (Phot. Rundschau, 1930, p. 74). It had been
mentioned earlier that Trail Taylor had used and described such lycopo-
dium.

7. Capt. Botton and Colomb constructed magnesium flares for night
signaling in the merchant marine; these flares burned for 3, 5, 8, 12, or 15
minutes (Phot. Archiv, 1865, p. 381).

8. See Jahrb. f. Phot. (1896), pp. 26, 423.

CHAPTER LXX1V

1. Compt. rend., X, 485.

792 NOTES TO PAGES 534-541

2. Ibid., 1839, VIII, 246.

3. Athenaeum, No. 670; Dingier, Polytechn. Journ., LXXVII, 467.

4. Repert. of Pat. Inv., Jan., 1844, p. 47. Dingier, Polytechn. Journ.,
XCII, 44.

5. Photo gr. Korresp., 1903, p. 230.

6. Blanquart-Evrard is also the inventor of albumen papers for photo-
graphic prints. This is erroneously ascribed to Le Gray or Talbot by
writers not familiar with the facts.

7. Eder, Jahrb. f. Phot., 1888, p. 440 (with portrait).

8. Phot. News, 1882, p. 300.

9. An exhaustive history of celloidin and aristo paper is published in
Handbuch, 1928, Vol. IV, Part 1 (Fritz Wentzel).

10. Handbuch, 1928, IV(i), 144.

11. Photogr. Korresp., 1900, p. 317.

12. E. Valenta, Phot. Korresp., 1900. York Schwartz, in Hanover, ap-
plied for a German patent on April 6, 1902, for a printing-out paper with
a silver phosphate emulsion.

13. Eder, Jahrb. f. Phot., 1893, p. 53.

14. I copy here the statement in Blanquart-Evrard’s La Photo graphie,
ses origines, ses progres, ses transformations (Lille, 1870), p. 182. Ignorant
of this source, I cited Le Gray’s priority in 1850 for the gold toning of
paper copies, in Handbuch, 1 899, IV, 6.

15. Valicourt, Manuel de Phot., 1851, p. 345.

16. Eder, Jahrbuch f. Phot., 1895, p. 484.

17. Alphonse Davanne (b. 1843, d. 1912) was distinguished bv his re-
search in the field of photography. He was an amateur photographer with
a studio in his own private house. He laid the basis for our knowledge of
the chemical changes during the photographic copying process with sil-
ver chloride. He was active in the progress of photolithography, a found-
er of the French Photographic Society, one of the presidents of the In-
ternational Congress for Applied Chemistry in Vienna, 1898 (Photo-
graphic Section) and of the French Photographic World Exposition. He
wrote: La Photo graphie', traite theorique et pratique (1886-88); on Nice-
phore Niepce (1885); on Poitevin (1882); on Gillot (1883); report on
the World Exposition in Vienna (1873), etc.; with Louis Barreswil and
others Handbuch d. Phot. (1854, German ed., 1863-64).

18. Bull.Soc.. franp., 1902, p. 223.

19. Photogr. Korresp., 1902. p. 650.

CHAPTER LXXV

1. Engl, patent, No. 100,098; Brit. J. Phot., 1917, p. 303.

2. Traube’s English patents are: Nos. 147,005; 163,336; and 163,337.
Traube’s American patent is No. 1,093,503, dated 1914.

793

NOTES TO PAGES 542-553

CHAPTER LXXVl

1. John Herschel, “On the Action of the Solar Spectrum,” Phil. Trans.
1842; also Photogr. Archiv, 1864, p. 467.

2. Photogr. Korresp., 1897, p. 78.

3. According to Pizzighelli and Hiibl (Die Platinotypie, 1883) the salts
of iridium produce no image with this process, while with palladium salts
nice brown pictures are obtained.

4. Phot. Korresp., 1887 and 1888.

5. Phot. Korresp., 1894, p. 518.

6. Hiibl, Der Platindruck, 1895; also Phot. Korresp., 1894, p. 555.

7. Wilhelm Glotz contributes to the Kartogr aphis che Zeitschrift
(Vienna), 1922, Vol. X, an article on the centenary (1818-1918) of the
Vienna Military Geographic Institute.

CHAPTER LXXVII

1. G. Douglas elaborated photographic tracing on zinc plates in 1920
at the English-Egyptian Cartographic Institute, Cairo, and published the
details of what was called the “Douglasgraphy.”

CHAPTER LXXVI11

1. The chemical factory of Van der Grinten, in Holland, also pro-
duced black tracing papers with special diazo mixtures; they were pat-
ented in England and France (March 23, 1927), but not in Germany,
owing to precedence of Kalle’s patents (see Eder and Trumm, “Licht-
pausverfahren,” in Handbuch, 1930, IV(4), 230).

CHAPTER LXXIX

1. Mungo Ponton, b. 1801, d. August 3, 1880, in Clifton, England.

2. Edinb. New Philosoph. Journ., 1839, p. 169.

3. In making this statement we must consider many superficial and er-
roneous reports of the historical development of photography with
chrom salts, which state that Ponton is called the discoverer of the sen-
sitivity of gelatine chromate to light. Many errors of this sort, relating to
the use of chromates in photography, are copied by some writers from
other authors and so disseminate the errors in literature by repetition.
This incorrect statement is printed in the unreliable Geschichte der Pho-
togr aphie (1891), by Schiendl, which Eder properly corrected in Pho-
togr. Korrespondenz (1891, p. 151).

4. Hunt’s Researches on Light (1854), p. 175; Athenaeum (1843), No.
826; Dingier, Polytechn. Journ., XC, 413.

5. See Hunt, Manual of Photogr. (1854).

794 NOTES TO PAGES 553-559

6. Compt. rend.., XXXVI, 780; Dingier, Polytechn. Journ., CXXVIII,'
296.

7. India ink was known as a dyestuff (see Simpson, Swan's Pigment-
druck., German ed. by Vogel, Berlin, 1868, p. 10).

8. Poitevin, we must note, also applied for a patent, December 13, 1855,
for his photogalvanic method— manifestly later than Pretsch.

9. A portrait of Alphonse Louis Poitevin appeared in Paris-Photographe
(1892).

10. Phot. Archiv (1882), p. 94; Phot. Korresp. (1882), p. 94; also,
Poitevin, Traite des impressions photogr. (Paris, 1883, 2d ed.).

11. Bull. Soc. franp. phot. (1856), p. 214.

12. Seely, the publisher of the American Journal of Photography, also
proposed the use of chromated gum (1858) without adding anything new
to the problem.

13. Bull. Soc. franp. phot. (1862), p. 99.

14. Eder, Handbuch (1926), IV(2), 38.

15. Bull. Soc. franp. phot. (1858), p. 213; Liesegang, Der Kohledruck
(1884), p. 8.

16. Bull. Soc.. franp. phot, (i860), p. 314. Poitevin sued Fargier, or
rather the licensee Charavet, for infringement on his patent and won the
suit (Brit. Journ. Phot., 1865, p. 304).

17. Obituary in Eder’s Jahrb. f. Phot. (1915-20), p. 22.

18. See Swan, “Mein Anteil am Verfahren zur Herstellung von Kohle-
bildem” (Jahrbuch f. Photographie, 1894, p. 275). For the biography of
Swan see Brit. Journal (1904), p. 990; also, the monograph on the life and
works of Swan.

19. Edgar Hanfstangl (b. July 15, 1842, in Munich, d. in Munich May
29, 1910) owned from 1868 the “Franz Hanfstangl, kgl. bayr. photogra-
phische Hofkunstanstalt und Kunstverlag in Miinchen.” He was one of
the first to use the eosin silver wet collodion process as practiced with A.
Braun’s or H. W. Vogel’s bath methods for his reproductions of paint-
ings. He used a large turntable for his exposures, which he preferred to
make by direct sunlight. See Ch. LXXXVI regarding Edgar’s father
(Franz Hanfstangl).

20. The jury which awarded this prize consisted of: the president of
the Vienna Photogr. Gesellschaft, Regierungsrat Professor Dr. Emil Hor-
nig; the vice-president of the society, Von Melingo; Schriftfuhrer Hof-
photograph Professor Fritz Luckhard; Hofphotograph Viktor Angerer;
Supervisor Franz, of the Banknotenfabrikation der Osterreichisch-ungar-
ischen Bank, Vienna; also Captain G. Pizzighelli, photographer and chem-
ist, Dr. Szekely, in Vienna, kais. Rat Anton Martin, the chemistry profes-
sor Dr. Alexander Bauer of the Technische Hochschule, Vienna, the re-

NOTES TO PAGES 559-564 795

production technician Professor J. Husnik, Prague, Jos. Leipold, super-
visor of the government institution for cartography (reproduction sec-
tion), and G. Scamoni of the Imperial Russian delegation for the production
of government securities in St. Petersburg.

2 1 . The sensitivity to light of gelatine chromate in the spectrum (max-
imum 470 to 430 in blue and violet) was determined later by Eder
(Z eitschr. f. Physik, 1920, XXXVII, 235).

CHAPTER LXXX1

1. H. F. Farmer, mentioned here, who died January 4, 1926, is not to
be confused with E. Howard Farmer (Ch. LIX and Ch. LXXXI 1 I) who
at this time (1931) lives in London, about 70 years of age. The note in
Jahrb. f. Phot. ( 1921-27), p. 105, is due to a mistake in names. H. F. Far-
mer spent a great deal of his life in Patagonia, but returned later to Lon-
don, where he worked assiduously in photography.

CHAPTER LXXXll

1. Rawlins was born in 1876, in Kiverpool, where he received his sci-
entific education at the university; afterward he devoted himself to sculp-
ture. He took an early interest in photography. He exhibited his work
often at the Photographic Salon in London.

CHAPTER LXXX1I1

1. E. J. Wall was a chemist who occupied his time intensively with
photography. He spent his early years in London, where he. published,
in 1889, a photographic technical journal, The Photographic Answers. In
this periodical he undertook, among other subjects, to translate Eder’s
Photographie mit Bromsilber gelatine (Vol. Ill of Eder’s Handbuch d.
Phot., chapter “Herstellung von Emulsion”). He also translated into Eng-
lish the work of Fritz, Lithographie, E. Konig’s Farbenphotographie, and
Mayer’s Bromoldruck. He was the publisher of the Photographic News
from 1896. Later Wall became teacher of three-color photography at the
London Council School of Photo-engraving. He was also active in the
photographic industry. He came to the United States in 1910, engaged by
the Fire-proof Acetylcellulose Co., Rochester, worked with Technicolor
Motion Picture Co., Boston. In his last years he worked exclusively in
publishing photographic literature. He was assistant editor of American
Photography, Boston, where he built up the most important photographic
publishing house in the United States. Wall’s most important works are
The History of Three-Color Photography (1925, 732 pages); Practical
Color Photography (Boston, 1922, 1928); Photographic Emulsions

79 6 NOTES TO PAGES 566-572

(1929); Photographic Facts and Formulas (1929), and other works. He
died in Boston (Mass.), October 13. 1928.

CHAPTER LXXXIV

1. Compare Lafon de Camarsac, Application de I’heliographie aux arts
ceramiques aux emaux, a la joaillerie, aux vitraux ou transformation des
dessins photographiques; memoire presente a I’academie des sciences
(Paris, 1855); Lafon de Camarsac, Portraits photographiques sur email ,
(Paris, 1868).

2. Bull. Soc. franp. phot. (July, 1858), p. 220.

3. See Martin, Handbuch der Emailphot. (1867), p. 49.

4. On modem methods see Schwier, Flandb. d. Emailphotographie, 3d
cd. (Weimar, 1885).

5. Compare Phot. Korresp. (1871), p. 55, and (1895), p. 544.

CHAPTER LXXXV

1. Other unsubstantiated claims for priority were fought by Auer in
his brochure, Das Benehmen eines jungen Englanders (Vienna, 1854). He
discusses there the fact that in 1852 the Englishman Henry Bradbury had
learned to know from Auer, in Vienna, the process of nature prints and
then illegally claimed for himself the priority for the invention (see
Wurzbach, Neue freie Presse, from July 30, 1869).

2. See the publication on the occasion of the celebration of the cen-
tenary of the Government Printing Office, Vienna, 1904; for the biog-
taphy of Auer see Professor Arthur W. Unger’s, Die Geschichte der k. k.
Hof- und Staatsdruckerei, Archiv f. Buchgew. (1905) February and
March issues; and Wurzbach in Neue freie Presse of July 30, 1869.

3. In the Vienna Hof- und Staatsdruckerei appeared the following
works illustrated with nature prints: C. v. Ettingshausen, Photographi-
sches Album der Flora Osterreichs, zugleich ein Handbuch zum Selb-
stunterricht in der Pflanzenkunde, with 173 tables (Vienna, 1864). Die
Blatt-Skelette der Dikotyledonen mit besond. Riicksicht auf Untersu-
chung u. Bestivrmung d. fossilen Pflanzcnreste, with 276 physiotypes
printed in the text and a map with 95 color charts and 1,042 nature prints
(Vienna, 1861); Vb. Castanea vesca u. ihre vorwelt. Stavrmart , with 17
tables of nature prints (1872); Ettingshausen and Pokomy, Physiotypia
plantarum austriacarum. Der Naturselbstdruck in sein. Anwendung auf
d. Gefdsspflanzen d. Osterreichisch. Kaiserstaates, mit besonderer Beriick-
sichtigung der Nervation in den Flachenorganen der Pflanzen, Vols. I-V,
tables 1-500 (Vienna, 1856).

4. Freiherr Ignaz von Plener was an influential Austrian official of the
Department of Finance, who became later the head of it; still later he be-

NOTES TO PAGES 573-575 797

came minister of commerce and member of the upper house of the Legis-
lature. During the time when this party was in power the Government
Printing Office was greatly cramped in its efficiency, but it survived. The
famous old Imperial Vienna Porcelain Factory, more than 100 years old,
fared worse. This was entirely discontinued, much to the sorrow of later
generations. It was not until after the World War that the factory was
rebuilt.

5. Carl Auer von Welsbach (b. September 1, 1858, in Vienna, d. Au-
gust 4, 1929, in Schloss Welsbach) achieved the invention of the incan-
descent gas light in 1885, based on his studies of alkaline earths. He in-
vented the osmium incandescent lamp and the pyrophore cer-iron. His
biography, written by Eder, appeared in the Z eitschrift des niederdsterr.
Gevoerbevereins, Vienna (1929), a society of which Auer was an honor-
ary member. It was Eder who undertook the spectrum analysis research
of Carl Auer’s cracked and decomposed alkaline earths.

CHAPTER LXXXVI

1. Franz von Kobell, Die Galvanographie, eine Methode, gemalte
Tuschbilder durch galvanische Kupferplatten im Drucke z u vervielfdl-
tigen (Munich, 1842; 2d ed., Munich, 1846). See also the discussion of
Kobell’s inventions in Martin’s Repertorium der Galvanoplastik und Gal-
vanostegie (1856). Also Eder’s Handb. d. Phot., 1922, Vol. IV, Part 3.

2. See Alois Dreyer, Franz von Kobell, sein Leben und seine Dichtun-
gen, Munich, 1904.

3. Martin, Repertorium der Galvanoplastik und Galvanostegie (Vienna,
>856), p. 123.

4. See Martin.

5. Franz Hanfstangl advanced lithography in Germany to its great de-
velopment; he published many lithographs, designed and drawn on stone
by his own hands; he reproduced 190 large paintings of the Dresden mu-
seum at government expense. In 1848 he devoted himself zealously to the
electrotyping process named after him.

6. For biography of Franz Hanfstangl with portrait see Leipziger 11 -
lustrierte Zeitung (March 10, 1904).

7. Franz Theyer, of Vienna, exhibited electrotypes at the 21st meeting
of German scientists and physicians in Graz. With Dr. E. Weidele he es-
tablished, 1842, in Vienna a laboratory for galvanoplastic (electrotyping-
plating). See V erzeichnis der bei der 21. Versammlung deutscher Natur-
forscher und Arzte in Graz ausgestellten Produkte der Galvanoplastik
aus Theyers Laboratorium.

8. “Versuch der Wiederbelebung durch Hubert Herkomer und Henry
Thomas Cox,” in Eder, Jahrb. f. .Phot. (1897), p. 479.

798 NOTES TO PAGES 577-584

CHAPTER LXXXVU

1. In Vienna are preserved such etched daguerreotype gravure plates,
dating from 1843 (reproduction of the painting “Palace with Ornamenta-
tions”), signed: “After Prof. Berres’s etched daguerreotype by Jos. Ax-
mann.” For more information about Axmann see Bodenstein, Hundert
Jahre Kunstgeschickte Wiens in den Regesten, 1898.

2. A. Martin, Repertorium der Photographie (1846), II, 75.

3. In the 1905 German edition of this History a facsimile in gravure is
bound in as Table III. In the 4th German edition (1932) this is repro-
duced in halftone.

4. Excursions daguerriennes consisted of 1 14 illustrations, which cost
1 14 francs; each of the prints could be purchased separately for one franc.

5. The attention of the author was called to this article by Pretsch by
Mr. Edgar Hunter, managing director of the Printing Press Firm, Lon-
don, 26-29 Poppings Court, Fleet Street, in a letter dated June 20, 1908.

6. Government Printing Office.

7. See Fizeau, Vervielfdltigung der Lichtbilder durch Abziehen einer
galvanischen Kopie eines Daguerreotyps ; Martin, Repertorium der Phot.
(1846), I, 120; (1848), II, 100; also Dingier, Polyt. Journ., LXXX, 155;
XCIII, 216.

8. In 1848 Becquerel (Compt. rend., XXVII, 13) made the same obser-
vation.

9. Poitevin, Traite de Vimpression photographique (Paris, 1862), pp.
4-9.

CHAPTER LXXX VIII

1. See Wurzbach, Lexikon, XXIII, 280; also Fritz, Festschrift zitr Ent-
hullungsfeier der Gedenktafel fur Paul Pretsch (Vienna, 1888, printed
privately bv the “Verein der Wiener Buc.hdrucker und Schriftsetzer
Wiens”), Phot. Korr., 1874, p. 47.

2. This London World Exhibition included for the first time exhibitors
from different countries.

3. Pretsch never published the details of his method. However, we
know them accurately from the publications of his pupil Leipold, Direc-
tor of the Government Printing Office in Lisbon (Phot. Korresp., 1874,
p. 180; compare also Phot. Korresp., 1874, p. 46).

4. D e la Rue was the first to use the collodion process in photography
successfully during the eclipse of the sun, on July 18, i860.

5. Negre’s photogalvanographs were exhibited at the London World
Exposition, but they were then imperfect, showing hard edges and coarse
middle tones (H. W. Vogel, Die Photographie auf der Londoner Weltaus-
stellung, 1862, Brunswick, 1863, p. 38).

NOTES TO PAGES 586-591 799

6. Georg Scamoni’s biography is printed in Chapter XCVI. It is of his-
torical interest to note the helio-galvanoplastic process which he used.
This process depended on collodion negatives strongly intensified with
mercury chloride, silver nitrate, and pyrogallic acid. Scamoni’s predeces-
sor, the Englishman Osborne, used this process and produced such pho-
tographic reliefs, silver plated with tinfoil (Phot. Archiv, 1864, p. 271).

7. Bull. Soc. frang. phot. (1862).

8. Harrison, A History of Photography (London, 1888), p. 135; see
also British Journal of Photography (1885), pp. 167, 581, 596, and The
Photographic News (1885), pp. 578, 600.

9. J. W. Swan had the same idea and at about the same time withdrew
his claim; however, he accorded Woodbury priority because the latter
had first made his invention public (see Phot. News, 1865, pp. 387, 397,
489, 502, 512).

10. It was necessary to trim Woodburytypes and to mount them on
cardboard, owing to the adhering smudgy edges.

11. Emil Mariot was born January 7, 1825, in Kromau, Moravia, and
died in Vienna on August 7, 1891. His portrait and biography are pub-
lished in Hornig’s Jahrb. f. Phot. (1885). Obituary, Phot. Korresp.
(1891), p. 398 (with picture), also Phot. Rundschau (1891), pp. 107, 383.

12. Tbe Austrian one hundred and one thousand gulden banknotes, as
well as the later twenty kronen notes (1900), and other banknotes, were
printed from electrotypes.

CHAPTER LXXXIX

1. Steel plates were used as early as 1820 for steel engravings by the
Englishman Charles Heath. Same size reproductions on steel (after the
manner of litho-transfers and their etching method) were probably de-
scribed first by Jonas, in Frankfurter Gewerbefreund (1842).

2. See Hand buck (1922), Vol. IV, Part 3.

3. Aquatinta-Manier: Joh. Heinr. Meynier states in his Anleitung zur
Atzkunst (1804) about this: “The Aquatinta-Manier differs from the or-
dinary art of etching and crayon manner in that the shading is not pro-
duced either by cross-hatching or stippling, but, if I may be permitted to
say so, by a ground of rosin, with which the plate is dusted and which
forces the acid to bite the copper to quite a rough surface. Stopping out
(covering) varnish and rosin varnish are painted on to permit the acid
work only where shading is to be,” etc. At first the rosin was dusted on
the plate through an ordinary sieve, and therefore Meynier claims to have
been the first to have used the co-called “dusting box.” He himself states,
however: “I have my doubts that I may justly claim the invention of this
machine, for I learned subsequently that other workers in aquatint use

800 NOTES TO PAGES 591-599

similar boxes although I never saw one.” This so-called dust grain has
lately been used on collotypes. See also K. Kampmann, “Titel und Namen
der verschiedenen Reprodukdonstechniken,” in Osterr.-ungar. Buch-
druckerzeitung (1891).

4. Niepce de Saint-Victor, Traite pratique de gravure heliographique
(Paris, 1856), p. 44.

5. Negre also invented the decorations for and on metal ( sort of dam-
ascene lace effect) by photography. He copied designs on metal, coated
with asphalt, developed them and goldplated them galvanoplastically. He
also produced in the same manner intaglio plates (Bull. Soc. franp. phot.,
1856, p. 334; Kreutzer’s Jahresber., 1856, p. 1 1 9 ).

6. See La Lumiere (1854), pp. 159, and (1885), p. 43.

7. La Lumiere (October 21, 1854), p. 165. A beautiful collotype by
Ch. Negre appears in Monckhoven, Traite general de photographie (2d
ed., 1856).

8. Cosmos, Revue encycloped.. Ill, 615; Liebig's Jahresbericht (1854),
p. 202; Kessler, Photographie auf Stahl, Kupfer usw. (Berlin, 1856).

CHAPTER XC

1. In the previous edition of this History (3d ed.) Talbot’s “Photo-
glyph” (illus. 299) is reproduced by collotype. In the 4th ed., on page
850, a halftone plate is printed.

2. See Handbuch, IV, 499; also Phot. Korresp. (1867), pp. 191, 193. H.
Gamier exhibited collotype copper etchings made by the chromate proc-
ess, which he kept secret. He probably proceeded along the way pre-
scribed by Talbot (chromated gelatine plates etched in iron chloride),
with some improvements; also, probably he introduced the double or
multiple copying of lights and shadows of the image and the multiple
etching process, however, this author can only conjecture this.

3. This coincides with the introduction of silver bromide collodion
emulsion for orthochromatic negatives.

4. Karl Klic’s name is not on the official list of regular students at the
Academy of Fine Arts in Prague.

5. The licensed firms which had purchased Klic’s process kept it very
secret, but the manipulation of the method gradually filtered through the
workmen into public knowledge. In 1886 Hans Lenhard, an employee of
J. Lowy, in Vienna, who was not connected with the collotype depart-
ment, but achieved inside information from workmen, published the de-
tails of the process in the periodical edited by him, Der photographische
Mitarbeiter. This was followed in the publication by Rudolf Maschek of
the Military Geographic Institute in Vienna of the Klic process in Eder’s
Jahrb. f. Phot., 1887 and 1891, and soon after this date other publicity
followed (see Handbuch, 1922, Vol. IV, Part 3).

8oi

NOTES TO PAGES 599 - 609

6. In 1881 Victor Angerer, who conducted a large art institute in
Vienna, introduced Klic’s process, producing collotypes for the annual
report of the Imperial Art Collections. His son-in-law, the copper etcher
Blechinger, increased the business considerably, with V. Angerer in the
following year, and alone after 1886. In 1893 Blechinger (with Leykauf
and later with Raimund Rapp) introduced collotypes with great success,
which until that time were produced by Boussod and Valadon in Paris,
almost alone.

7. The German word Rakel (“doctor,” in English) is derived from
the Low German rak which means straff (taut). A tightly stretched,
thin steel band with a knife edge is attached on rotogravure presses and
removes from the surface of the gravure cylinder any excess of printing
ink. The doctor was first used in printing of textile goods, carpets, and
wallpaper. In modern speed printing presses for rotogravure, the doctor
is decidedly important.

8. Adolf Brandweiner (b. February 26, 1866, in Suchenthal, Bohemia)
attended a technical school at Salzburg, 1883-84. He was then employed
in the Rentsch reproduction establishment, Dresden, and in Sacb’s En-
graving Company, and in Manchester. Later he assisted in the introduction
of the rotogravure process in the cotton print factory Cosmanos, in Josefs-
tal, Bohemia. During the summer of 1891 he was a student at the Graphische
Lehr- und Versuchsanstalt in Vienna, where he perfected his process of
employing the “doctor” in rotogravure and where he also presented his
results before the Vienna Photographische Gesellschaft (Phot. Korresp.,
January, 1892).

9. The president of the Vienna Kunstdruck A. G. was Kommerzialrat
Albert Rott (d. May 27, 1931) the director of the factory, Kovac. The
building was erected in the garden of the former plate factory of J. Lowy
fronting on Parkgasse 15-19.

10. In his last years Th. Reich was employed by Wiener Bilder as su-
perintendent of the rotogravure printing plant. His portrait was printed
in that periodical on October 4, 1931.

11. The process consisted in copying a positive on silver bromide
gelatine paper by exposing it for a few seconds under an electric light.
Then a screen was copied on it, the print was developed in amidol, im-
mersed as in the bromoil process in a bleaching bath. It was then squeezed
onto the copper plate, and the insoluble silver image was brought out
with warm water. It was etched in perchloride of iron acid solution.

CHAPTER XCI

1. The detail of this method was published by Lemercier, Lerebours,
Barreswil, and Davanne in February, 1854, in Bulletin de la Soc. d'En-

802 NOTES TO PAGES 609-614

couragement (1854, p. 84); see also Handbuch, 1922, IV(3), 356;
also Dingier, Polytechn. Journ., CXXXII, 65, and especially Barreswil and
Davanne, Die Anwendung der Cbemie auf die Photographie (German by
Schmidt, i860), p. 461.

2. An example is preserved in the collection of Graphische Lehr- und
Versuchsanstalt in Vienna.

3. See Poitevin, Traite de /’ impression photogr. sans sets d’ argent
(Paris, 1862), p. 79. Poitevin, Bull. Soc. frang. de phot. (February, 1857).
English patent, February 23, 1858, No. 357; Snelling’s Photographic and
Fine Art Journal (1858), p. 337.

4. La Lumiere (1856), p. 54; Horn, Phot. Journ. (1856), VI, 10.

5. Gottlieb Benjamin Reiffenstein (b. Sept. 10, 1822, at Colleda, near
Erfurt; d. March 27, 1885, in Vienna) frequented the Royal Art School
at Erfurt. He came to Vienna in 1842, found a position in the studio of
the professor of architecture, Ludw. Forster, where he worked on draw-
ings and copper etchings for Forster’s published works. With Ludw.
Rosch he bought the lithographic business of Joh. Rauh, Vienna, which
soon prospered as Reiffenstein & Rosch, owing to the former’s artistic
talent and Rosch’s business ability. In the early sixties he became inter-
ested in photography, and with Karl von Giessendorf he endeavored to
introduce photolithography, especially by the asphalt process, into his
company. His splendid success is shown by the examples exhibited at the
first photographic exhibition in Vienna (1864). After GiessendorPs
death, in 1866, he continued the work in the same field with Ludwig
Schrank. Uninterruptedly the asphalt process was carried on; the half-
tone process was elaborated into the manufacture of three-color plates
after the system of Ducos du Hauron. The difficulties which he met
owing to insufficient prevailing knowledge of color filters seemed insur-
mountable and were so discouraging that Reiffenstein turned, aided and
abetted by his artistic staff, entirely to manual chromolithography. His
work stands eminent in the reproduction of the old and modern masters
of fine arts, true to the original paintings and as commercially required by
the taste of that period.

6. See Kampmann, “Geschichte der Photolithographic mittels Um-
druckpapieres” (Eder, Jahrbuch f. Photogr., 1896, p. 293).

7. Annuaire general et international de la photogr. (1895), p. 141.

8. History of zinc plates for flat press printing, see Kampmann, Phot.
Korresp. (1890), pp. 267 ff.

9. Paper was coated with chromated gelatine, on which a negative was
copied, rolled up with greasy ink, and developed in water with a sponge.
There remains the image in greasy transfer ink of the portions exposed to
light.

NOTES TO PAGES 614-619 803

10. See the periodical Engineering (June, 1888); Eder, Jahrbuch f.
Phot. (1889), p. 67.

1 1. See British Association, Report of the Meeting (1861), p. 263; also
Brit. Journ.-Phot., VII, 240; Kreutzer’s Z eitschriftf. Phot. (1861), III, 24.

1 2. Eder, “Beitrage zur Geschichte und Theorie der Algraphie” (Eder,
fahrb. f. Phot., 1908, p. 132).

13. The process of copying halftone negatives directly onto aluminum
plates coated with albumen or chxomated fish glue (“algraphische Auto-
typie”) was first completed by Regierungsrat Fritz, assistant director of
the Government Printing Office in Vienna and published in Phot. Kor-
resp.

14. Langenheim’s so-called “hyalotype” process (Ch. xli) is not related
in any way to that of Hann.

15. Karl Kampmann came from a middle-class Viennese family. He
was the son of a master glazier, Lorenz Kampmann, bom July 8, 1847.
He worked at lithography and etching on glass and studied at the Gra-
phische Lehr- und Versuchsanstalt in Vienna, to which Director Eder
later appointed him teacher of photolithography. He wrote many articles
on lithography, photolithography, zincography, and on nature prints,
which he first published in Eder’s Jahrb. f. Photographie. His publica-
tions include: Die gr aphis chen Kiinste (Leipzig, 1898); Die Liter atur der
Lithographie von 1798 bis 1898-, Titel und Namen der verschiedenen Re-
produktionstechniken (Vienna, 1891); Geschichte der Lithographie und
der Steindrucker in Osterreich (1898). He retired in 1909, moved to Ba-
den near Vienna, where he died July 12, 1913. His biography, entitled
Karl Kampmann , by J. M. Eder, and examples of his lithographic works
were published in 1918 by the Graphische Lehr- und Versuchsanstalt in
Vienna.

CHAPTER XCll

1. See Phot. Korresp. (1868), p. 274.

2. The history of the invention of the collotype process and its varia-
tions is treated exhaustively in the brochure by August Albert, Die ver-
schiedenen Methoden des Lichtdruckes (1900).

3. J. Husnik and Carl Klic applied for an Austrian patent for the pro-
duction of printing plates for securities which could not be counterfeited,
on October 31, 1875 (Kl. IX, 234. N).

4. Phot. Mitteil. (1868 and 1870).

5. See Die Grossindustrie in Osterreich, Vol. VI; Geschichte der Pho-
tographie und der photomechanischen Verfahren, by J. M. Eder (1900).

6. Concerning “collotype by letterpress” see Arthur W. Unger, Phot.
Korresp. (1902), p. 152; Osterr.-Ung. Buchdr.-Ztg. (1902), p. 181; Ar-

804 NOTES TO PAGES 621-626

chiv f. Buchgew. (1902), p. 182. A. W. Unger, professor at the Graphi-
sche Lehr- und Versuchsanstalt in Vienna, referred in his writings also to
“Duplexlichtdruck” (duplex collotypes), as well as to the use of stereo-
types as carriers of the collotype gelatine.

CHAPTER XCIII

1. Relief etchings on copper, or ektypography, was the name which A.
Dembour, an engraver in Metz (Lorraine), called the relief process in-
vented by him in 1834. He made drawings on copper plates with greasy
varnish and etched away the bottom, which was not covered by the var-
nish. This is perhaps one of the first publications on the so-called relief
etching for letter press printing (German by H. Meyer, 1835, with 8 il-
lustrations). The use of galvanic baths for depositing metal, as an etching
ground, came from the Dane C. Piil. He called his process “chemitypy,”
which he described as follows in his work of 1846: “Zinc is a positive
metal. I cut or etch a design on such a polished zinc plate, and the depres-
sion created is filled in (melted in) with a negative metal. The original
positive zinc plate is now deepened by etching with a certain acid, and
the design, which at first seemed below the surface, appears now as a
raised die. This is possible only because the melted metal composition,
owing to the galvanic action agitated between the two kinds of metal, is
not affected by the acid, which attacks only the positive zinc.” Negre in-
vented, in 1867, a process in Paris, by which a steel plate, coated with
asphalt or bichromate of glue and having a photographic image copied on
it, was gold-plated in a galvanic bath. The gold, of course, was deposited
only on the bare portions of the plate; after the asphalt or glue ground
were removed. The gold image on the metal could be etched with the
proper acid (Phot. Archiv, 1867, p. 171).

2. As late as 1878 Morch proposed a similar way, trying to copy a half-
tone gravure plate on a grained transfer paper, which he proposed again
to transfer on zinc or stone (Phot. News, 1886, p. 761).

3. A. Albert, Verschiedene Reproduktionsverfahren (1900).

4. C. Angerer never published his process of etching zinc according
to what was called “nach der Wiener Methode.” It is, however, described
in exact detail in Morch’s Handbuch der C.hemigraphie und Photochemi-
graphie (Diisseldorf, 1886) alongside the French method, which was
somewhat different. The history of C. Angerer and Goschl, an engraving
firm, was published as a memorial on the 50th anniversary, 1871-1921.

5. The family of Carl Angerer in Vienna is not related to the brothers
Ludwig and Viktor Angerer, who are mentioned in Chapter XLIII.

6 . The process of transferring drawings on metal for etching is still
used, especially for industrial designs.

NOTES TO PAGES 626-631 805

7. C. Grebe, “Geschichte der Raster,” Z eitschr. f. Reproduktionstech-
nik (1899), p. 19; see also Gamble, in The Photographic Journal (1897),
p. 126.

8. Bull. Soc. frang. phot. (1859), pp. 116, 211, 265; Grebe (note 7
above), p. 21.

9. Burnett, Journ. Phot. Soc. (London, 1858), No. 74, p. 98.

10. Mathey (1864), Kiewic (1866), see Jahrbuch f. Phot. (1892), p.
474; also in Woodbury’s patent of December 4, 1872 (No. 3659), in
which negatives of mosquito netting were used: Jaffe (1877), Thevoz,
Gamble (see Grebe, Z eitschr. f. Reproduktionstechnik, 1899, p. 19); also
with crossed copper wire (ibid., p. 20). Woodbury discontinued the ex-
periment with mosquito netting.

11. Egloffstein, Abridgement of Specification Relat. to Phot. (London,
1872), p. 127.

12. Grebe; see note 7 above.

13. See Anthony’s Photographic Bulletin (1895), p. 136; Eder, Jahrb.
(1896), p. 470.

14. Swan, Phot. Korresp. (1866), p. 155.

15. Phot. News (1868), p. 355.

16. ([Max Jaffe died December 14, 1938, at the age of 93. An American
branch of the Vienna firm was established and incorporated at 40 East
49th Street in New York City under the name of Arthur Jaffe, Inc.—
Translator.]

17. On Jaffe’s construction of a glass studio see Handb. (1893, Vol. I,
Part 2), and supplementary volume, p. 34, illus. 40-41; also Phot. Korresp.
(1871), p. 57.

18. The history of “similigravure” is printed in Le Procede (1928), p.
48.

19. The term “autotypie,” designating the halftone letterpress process,
is not used in England, where it is called “halftone process”; in France it
is called “photogravure a demi-teintes” or “similigravure”; in Italy,- “mez-
zotinta.” For “Raster” the English use the name “screen,” the French
“trame,” the Italians “reticola.”

20. Heinrich Riffarth, the founder of the Berlin firm Meisenbach,
Riffarth & Co., was bom on August 10, i860, in Munich-Gladbach, where
his father was a publisher. After having been graduated from the gym-
nasium, he studied chemistry in the laboratories of Vienna and Salzburg
at the government technical high schools. The writings of Ducos du
Hauron, Tessie du Motay, and others urged him to proceed farther into
photochemical research, and he became one of the first pioneers and a
famous promoter of the photochemical reproduction technique in Ger-
many. He died January 21, 1908.

806 NOTES TO PAGES 632-637

21. Phot. Korresp. (1884), p. 180, and 1885, p. 454; Phot. Mitteil., XXI,
' 98 .

22. The earlier process, which Frederick Ives patented August 12,
1878 (see Phot. News, 1883, p. 498), consisted in blackening evenly a
photographic chromo-gelatine relief, which was transferred onto a raised
or grained paper; it then presented the appearance of a chalk drawing
and was again transferred to metal and worked up for letter press print-
ing. Proofs of this process of Ives are shown in Jahrbuch (1889), Vol. II.

23. For useful receipts see Eder’s Rezepte und Tabellen (6th ed., 1905).

24. The use of etching machines in the graphic arts is very old. In
Diderot’s great Encyclopedic of 1767 will be found the description of a
machine for copper etchings, in which the etching tub was agitated by a
clock movement. In 1856 Pretsch etched metal plates by blowing the
acid on them. Louis Levy sprayed the acid vertically onto flat plates. Later
other varieties of etching machines were put on the market.

25. Transactions of the Royal Society of Canada (1895), Vol. I, section
iii, p. 29; also Phot. Mitteil., XXXVI; Eder, Handb. d. Phot. (1928, Vol. II,
Part 4, “Autotypie” by Eder and Hay).

26. American fish glue is soluble in cold water and is produced from
the refuse of fish.

27. To complete the record: H. W. Hyslop, in American Journ. of
Phot., 1896, p. 362, claimed the priority for the copper enamel process.
His first publication and the description of the fish glue method appeared
in Artist Printer, Chicago, in October, 1892. S. H. Horgan, in Inland
Printer, 1929, LXXXIII, 107, took his part and believed Hyslop to be the
inventor of the fish glue enamel process.

28. Phot. Korresp. (1900), p. 562.

29. See Eder’s Jahrb. f. Phot. (1901), p. 222; also A. C. Angerer, “Cber
Komatzung,” Phot. Korresp. (1921), p. 251; R. B. Fishenden, Process
Engraver's Monthly (1909), p. 226; and the same in Process Year Book
(1917) Vol. XIX and (1920) Vol. XXII.

30. Husnik and Hausler, Kornautotypie mit ungefarbtem Glasr aster
(February, 1901); see also Jahrbuch (1901), p. 222.

31. Emanuel Spitzer applied for a patent (1901) in Berlin for his in-
vention, describing the development of an “Eigenkom” (specific grain)
which is produced in the light-sensitive bichromate glue top. According
to later investigations, small drops of glue solution are segregated, which
enter and dry in minute particles in the “top” and during the etch-
ing process form with the perchloride of iron a grain in the printing
surface. The patent office informed the inventor a short time after his
application: “There can be no mention of an ‘Eigenkorn’ (a specific
grain), therefore, the term ‘Korn’ (grain) must not be used in the patent

NOTES TO PAGES 639-647 807

application.” Spitzer fought for three years without result for his view-
point; his financial conditions forced him to give way in order to have
granted to him in 1905 what he dubbed his “mangled” patent. He etched
with iron chloride solutions.

CHAPTER XC1V

1. Georg Fritz, “Die Vorlaufer des Dreifarbendruckes und der Far-
benheliogravure,” in Eder’s Jahrb. f. Photogr. (1902), p. 44, gives a his-
tory of the beginnings of three-color printing. Typographical printing in
color dates back to the 16th century.

2. We follow here C. Grebe’s “Zur Geschichte der Dreifarbensyn-
thesen,” in Z eitschr. f. Reproduktionstechnik (1900), p. 130.

3. Gilbert, Annal. (1792), XXXIV, 10.

4. Helmholtz, Handbuch der physiologischen Optik (2d ed., 1896),
p. 364.

5. Poggendorff, Annal., LXXXVII, 45.

6. Brewster, Introd. ad. philos. natur. (1820).

7. Helmholtz, in Poggendorff, Annal., LXXXVI, 501.

8. Maxwell, see Brit. Journ. of p hot. (1861), p. 270; Kreutzer’s
Z eitschr. f. Photogr., V, 143.

9. The centenary of the birthday of .Maxwell was celebrated festively
at Cambridge University.

10. See Life of Maxwell by Campbell & Garnett (London, 1882); Pog-
gendorff, Bio graph. -liter ar. Handworterb. (1898), III, 889.

11. Wiedemann, Annal. d. Phys. (1888 and 1892).

12. Philosoph. Magazine (1888), Ser. 5, Vol. XIX.

13. Hertz, Gottinger N achrichten (1890).

14. Collen, Brit. Journ. of Phot. (October 27, 1865), p. 547.

15. Schrank, Phot. Korresp. (1869), pp. 199, 333.

16. Eder, Jahrb. f. Photogr. (1895), p. 329.

17. S. Wall, Eder’s Jahrb. (1914), p. 127.

18. Ducos du Hauron reported on September 6, 1875, to the Society
of Agriculture, Science and Arts in Agen that he made silver bromide
collodion plates sensitive to red with chlorophyll. He related that Ed-
mond Becquerel declared, following Vogel’s publication, that chlorophyll
showed a sensitizing action in the red end of the spectrum.

19. Otto Pfenninger (Eder, Jahrb. f. Phot., 1911, p. 11).

20. Potonniee, the French authority on the history of photography, in
his biography of Ducos du Hauron, leaves out of account the part which
H. W. Vogel played in the invention of three-color photography and
without which Du Hauron would not have been able to achieve success.

21. For Ducos du Hauron's patent for a camera intended to photo-

8o8 NOTES TO PAGES 647-655

graph simultaneously three images of one and the same object see Otto
Pfenninger in Eder’s Jahrbuch f. Phot. (191 1), p. 1 1.

22. The principle of the superimposition of several sensitive films or
films with impregnated dyes was often used in different forms. E. J. Wall,
in his History of Three-Color Photography (1925), p. 152, reports on
this in his chapter on “Bi-packs and Tri-packs.” We mention here only
G. Selle’s patent (1899); Dr. R. Stolze’s German patent, No. 179,743
(1905); O. Pfenninger’s English patent (1906); and F. E. Ives’ English
patent ( 1908). The “bi-pack” is of interest in Gurtner’s two-color system
(blue and orange), see German patent, Nos. 146,149 and 146,150 (1902),
and 146,151 (1903); also Eder’s Jahrbuch fiir Phot. (1904), pp. 18, 207.

23. The anaglyph principle led also to the realization of the plastic
film production. The onlooker wears spectacles fitted with glasses with
complementary colors for each eye. Two stereoscopic pictures are pro-
jected on the screen through the same color filters. Although these ex-
hibitions were repeatedly offered in public places, the process was too
awkward and troublesome for the spectator and did not become popular.

24. Phot. Korresp. (1905), p. 24.

25. Bull.. Soc. frang. phot. (1869), p. 177.

26. Ibid., p. 123.

27. Phot. Korresp. (1879), p. 107.

28. Bull. Soc. frang. phot. (1869), p. 179.

29. Compt. rend., LXXXVIII, No. 3, p. 119; No. 8, p. 378; Phot. Kor-
resp. (1879), p. 107.

30. See Ducos du Hauron’s brochure, Les Couleurs en photographie
(1869); also in German translation Phot. Archiv (1878), p. 132.

31. Phot. Archiv (1878), p. 162.

32. Also printed in Phot. Archiv (1878), p. 109.

33. Phot. Korresp. (1904), p. 251.

34. Vidal’s classical example in this field was acquired bv Dr. Eder for
the collection of the Graphische Lehr- und Versuchsanstalt in Vienna.

35. H. W. Vogel, Die Photographie farbiger Gegenstdnde (Berlin,
1885).

36. Phot. Mitt., XXVIII, 201; XXIX, 85; Phot. Korresp. (1893), p. 125.

37. E. Albert’s patent brought in its train protracted difficulties. See
Phot. Korresp. (1898), p. 107; also Bruno Meyer’s Sachverstandiger und
deutsches Reichspatent 64806 (Weimar, 1902).

38. Phot. Korresp. (1904), p. 369. For the production of large color
gravures the contact paper had to be reinforced by wire netting in order
to insure register.

39. Dr. G. Selle was a practicing physician in Berlin, had studied in
Vienna, Paris, and London. He became interested in three-color photog-

NOTES TO PAGES 659-665 809

raphy. In order to achieve the final color composition result, after making
the three separations, he poured chromated gelatine on collodion films, ex-
posed through the back and then immersed them in cold water. Then he
put them through their respective complementary color solutions, which
penetrated into the layers unaffected by light. These films he then super-
imposed. He recommended several variations for the dyeing of the three-
color separation positives, which he patented, as well as a chromoscope
(1903). In order to promote the commercial exploitation of his process,
he started the Graphische Kunstanstalt for polychrome photography in
Berlin, where he, about 1895, advertised his “Sellechromie,” which at
first attracted great attention. Although he received the Order of the Red
Eagle from Kaiser Wilhelm II for his achievements, his process never
went beyond the experimental stage, nor did it result in any commercial
profit. Selle died June 8, 1907.

40. Eder, Handbuch (1903) III, 710.

41. Capstaff’s English patent was acquired by the Eastman Kodak Co.
and patented by them in 1915 (No. 13,429).

42. For more concerning this see Valenta, Die Photogr. in naturlichen
Farben (1912, W. Knapp); also Wall, History of Three-Color Phot.
(1925), pp. 475, 503, and Raphael Ed. Liesegang, “Zur Geschichte der
Farbenrasterplatten,” in Jahrb. f. Phot., 1908, p. 147.

43. The first reproductions of autochromes by the three-color halftone
process were probably ordered to be made by the firm Lumiere in Paris.
In Germany the first reproduction of an autochrome (portrait) by the
three-color halftone process was made by the “Graphische Kunstanstalt
Joh. Hambock,” Munich. This was exhibited on October 2, 1907 (Edcr’s
Jahrb. f. Phot., 1918, p. 401). The journal Schiveizer Graph. Alitt. of
April 15, 1908, published the reproduction ■ of an autochrome portrait
subsequent to the one by Hambock. The reproduction of autochromes
by photoengravers became soon universal.

44. Concerning the camera and the projector for three-color cinema-
tography according to the system Szepanik see Spanuth and Honnhold,
Phot. Korresp. (1925), p. 12; S. Szepanik, “Cinematography in Natural
Colors,” (Brit. Journ., Colour Suppl., October 2, 1925, p. 38).

CHAPTER XCV

1. See Philosoph. Transact. (1840), p. 28; Athenaeum, No. 621.

2. Compt. rend. (1851, 1852, 1859, and ff.).

3. Niepce de Saint-Victor, Compt. rend., XXXI, 491.

4. For fuller details see also the report of Becquerel in the meeting of
the French Photographic Society on December 18, 1857; also Heinlein,

810 NOTES TO PAGES 665-671

Photo graphikon, p. 384; Dingier, Polytechn. Journ., CXXXIV, 123; Phot.
Arch. ( 1868), p. 300.

5. Niepce; also Martin, Handbuch d. Photogr. (1857), p. 311, 1st and
2d treatise.

6. Compt. rend. (1862), LIV, 281, 299; Kreutzer, Z eitschrift f. Pho-
togr., Ill, 5; also Heinlein, mentioned above.

7. See Phot. Korresp. (1867), p. 190.

8. Pure silver chloride becomes distinctly violet in ultraviolet, but in
the visible spectrum, it gradually turns to a gray-violet. However, if it is
first exposed to diffused daylight (the violet subchloride is thus pro-
duced) it will then reproduce the spectral colors, although yellow and
green will certainly be pale and barely visible (Becquerel, Phot. Arch.,
1868, p. 300)-

9. De Roth, Fortschritte der Photogr. (1868), p. 22; Compt. rend.
(1866), LXI, 1 1.

10. Bull. Soc. franp. phot. (1874); Photogr. Korresp. (1874) XI, 65.

11. Concerning R. Kopp’s invention see Eder’s Jahrb. f. Phot. (1892;
and 1893, p. 432).

12. Eder’s Jahrb. f. Phot. (1893), p. 432.

13. Experiment of Beauregard, Kreutzer, Jahresber. Photogr. (1857),
p. 302; Bull. Soc. franp. phot. (1857), p. 116; see also Diamond, Heinlein,
Photo graphikon, p. 390.

14. Simpson, Photogr. Korresp. (1866), III, 100.

15. See E. Valenta, Die Photographie in natiirlichen Farben mit beson-
derer Beriicksichtigung des Lippmannschen Verfahrens (1894, 2d ed.,
1912); see also Eder’s Jahrbiich f. Photogr. (1891), pp. 538, and (1892),
p. 332; see also Handbuch (1927) II( 1 ), 183 f f ., where an exhaustive study
on “photochromy” by Liippo-Cramer will be found.

16. Portrait and short biography of Wilhelm Zenker is found in Phot.
Rundschau (1895), p. 91.

17. O. Wiener’s treatise was printed in Annalen der Physik, n.f. Vol.
LV; also in Vogel’s Phot. Mitteilungen, Vol. XXXII; L. Weickmann
delivered a memorial address on O. Wiener before the Saxony Academy
of Science, 1927.

18. See E. Valenta, Photographie in natiirlichen Farben (1912).

19. See Eder’s Jahrb. f. Photogr. (1892), p. 326 (with illus.) .

20. Eder, Jahrb. f. Phot. (1894), p. 450.

21. E. Valenta, Phot. Korresp. (Sept., 1892), p. 435.

22. Professor Dr. Richard Neuhauss (b. October 17, 1855, at Blanken-
felde) studied medicine at Heidelberg and Berlin, made in 1884 a trip
around the world for anthropological studies. When he returned he be-
gan practice as physician in Gross-Lichterfelde and took up photography.

NOTES TO PAGES 671 -673 811

From 1894 to 1904 he edited the Photogr. Rundschau, after which he
made a long trip to German New Guinea. At the outbreak of World
War I he volunteered in the Medical Corps, was infected while active in
diphtheria barracks, and died in Berlin-Lichterfelde on February 9, 1915.
Among his works are: Photographic auf Forschungsreisen (1894); An-
leitung zur Mikrophotographie (2d ed., 1908); Die Farbenphotographie
nach dem Lippmannschen Verfahren (1898); Lehr buck der Mikropho-
tographie (3d ed., 1907); and Lehr buck der Projektion (2d ed., 1907).
Of especial importance were his works on “Farbenphotographie”
(bleaching-out process and Lippmann process). His many publications
in technical journals are listed in Eder’s Jahrbuch fur Photographic. His
portrait is published in Photogr aphische Korrespondenz (1915), p. 95.

23. Dr. Hans Lehmann, physicist and photochemist, devoted himself
to the development of interference photographv according to Lipp-
mann’s procedure. He invented various apparatus, constructed by Zeiss
in Jena. Later he became scientific collaborator at Ernemann-Werke
in Dresden. His specialty was scientific construction for cinematog-
raphy; he constructed the “time expander,” an addition to cinema ap-
paratus called by its manufacturers, the Ernemann-Werke, “Zeitlupe”
(ch. lxxi). He wrote Die Kinemato gr aphie (1911).

24. See Eder, Jahrb. f. Photogr. (1921-27), p. 482. The description of
this procedure of H. Lehmann-Jahr is found also in Handbuch (1930),
III ( 1 ) , 1 6 1 . H. Lehmann wrote often concerning the Lippmann pro-
cedure; for example, Lehmann, “Beitrage zur Theorie und Praxis der
direkten Farbenphotographie nach Lippmann und Lumiere,” Verhand-
lungen, Deutsch.-Physik. Gesellsch. (1907), Vol. IX, No. 26; “Inter-
ferenzfarbenphotographie mit Metallspiegel,” ibid. (1909), Vol. XI, No.
20; “Die Praxis der Interferenz-Farbenphotographie,” Phot. Rundschau
(1909).

25. See also the early works of Szepanik (also Phot. Korresp., 1925,
p. 12).

26. Later patents by Keller-Dorian are the British patent, No. 246,908,
of Dec. 23, 1914, and the French patent No. 52,336, of Jan. 20, 1920. See
also the reports of the “K. D. B.-Film” in the Bull. Soc. franp. phot.
(1923), p. 26, with colored table, in the Brit. Journ. of Phot. (1923),
Color Suppl., p. 10, and more recent references in Filmtechnik and Kino-
technik concerning kodacolor. See also Dr. Grote, “Geschichtc dcs Lin-
senrasterfilmes,” Phot, lndust. (1931), p. 1342.

27. J. G. Capstaff and M. W. Seymour, “The Kodacolor Process for
Amateur Color Cinematography,” Transact. Soc. Motion Picture En-
gineers, (1928), No. 36, XII, 940; also C. E. K. Mees, “Motion Pictures in
Natural Colors,” Camera Craft (1928), XXXV, 305) and Mees, “Ama-

812 NOTES TO PAGES 673-679

teur Cinematography and the Kodacolor Process,” Journ. Franklin lnstit.
(Jan., 1929). The description of this process for the demonstration of
surgical operations and so forth is given by H. B. Tuttle in Journ. Soc.
Mot. Piet. Engin. (Aug. 1930), XV, 193.

28. A kodacolor film was produced in the Vienna Photogr. Gesellschaft
on Jan. 27, 1931.

29. Herschel, “On the Action of the Rays of the Solar Spectrum on
Vegetable Colours,” Philosophic. Transact. (1842); see also Hunt, Re-
searches on Light (1844), p. 170.

30. Photogr. Archiv (1893), Nos. 729-730.

31. Neuhauss, Phot. Rundschau (1903), p. 258.

32. Moniteur de la Phot. (1895); Jahrb. f . Phot. (1896), p.499.

33. See Jahrb. f. Phot. (1902), p. 544; Phot. Korresp. (1902).

34. See Jahrb. j. Phot. (1903), p. 48.

35. Phot. Korresp. (1902).

36. F. Limmer, Das Ausbleichverfahren (Verlag W. Knapp), 1911.

CHAPTER XCVI

1. The early photographic literature of the craft from 1839 to i860
was recorded by Ernst Amandus Zuchold, editor and publisher, in his
Bibliotheca photographica (Leipzig, i860). His data are unfortunately
not very dependable, especially regarding the earliest publications. Hor-
nig, in his Photograph. Jahrbuch (1877 ff.), lists the literature up to the
eighties of the 19th century. The meritorious president of the Vienna
Photographische Gesellschaft, Regierungsrat Professor Dr. E. Hornig,
spent a great deal of time and labor in collecting this data. We are in-
debted to Professor Erich Stenger, Berlin, for a complete enumeration of
the photographic literature from 1839 to 1870 in the German, French,
and English languages. The list appeared serially in Die photographische
Industrie.

2. Complete set of this publication was procured by Dr. Eder for the
library of the Graphische Lehr- und Versuchsanstalt in Vienna.

3. The name comes down from the famous French Estienne family of
printers and scientists, whose printing shop was established in 1501. The
last of this printer family, which became extinct in the 18th century, was
Antoine Estienne (1592-1674).

4. Paul Montel is the publisher of the Revue frangaise de photographie
et de cinematographic, Paris, and of other photographic publications. L.
P. Clerc is the editor of La Technique photographique and editor-in-chief
of the most important French authoritative photographic periodical, Sci-
ence & 'Industrie photographiques, both published by Montel.

5. Journ. Phot. Soc. (London, 1856), III, 48.

NOTES TO PAGES 679-687 813

6. Concerning The Daguerreian Journal, Vol. I, 1850, see Canfield, in
Phot. Times (1887), p. 648; it came into the possession of Humphrey in
1852. Elsewhere the contents of the Journal are discussed.

7. The report of the jury for the section “Photography” at the Uni-
versal Exhibition in Paris, 1855 (reporters Benj. Delessert and Louis Ra-
vene) was published in 1857 (see La Lumiere, 1857, pp. 43 ff.). Fritz
Hansen also reported on the exhibition, in Phot. Korresp. (1921), p. 176.

8. K. J. Kreutzer was called to Graz in his later years as librarian,
where he committed suicide during a mental disorder in 1863. The library
official Lukas of the Wiener Polytechnik continued to edit the periodical
started by Kreutzer, with whom he had previously worked on it. The
publication ceased in 1864.

9. For the history of the Photographic Society see Phot. Korresp.
( 1 9 1 1 ) . There the charter members are listed and the portraits of the fol-
lowing gentlemen are printed: Petzval, Voigtlander, Anton Martin, Joh.
Bauer, E. Homig, O. Volkmer, Fritz Luckhard, Ludw. Schrank, Ludw.
Angerer, Carl Angerer, Max A. Davanne, J. M. Eder, Wilh. Burger, A.
v. Obennayer, J. Hofmann, v. Hiibl, Perlmutter, Alex. Angerer, M.
Frankenstein, E. Forster, C. Pietzner, O. Prelinger, E. Sieger, F. Hrdlicka,
H. Kosel, W. Muller, E. Valenta, Mathilde Lowy, Prof. Berlin, Albert
Freiherr v. Rothschild, E. Bondy, and C. Seib.

10. Obituary of Ludwig Schrank in Phot. Korresp., June, 1905.

11. Asa memory of the first German photographic exhibition (1864)
the Wiener Photograph. Gesellschaft organized, forty years later, a great
exposition in the Austrian Museum for Art and Industry. The last great
international photographic exhibition before World War I took place in
Dresden in 1909. This was followed by an International Exposition for
the Book-publishing Trade and the Graphic Arts (Bugra) in Leipzig
in 1914. This was greatly curtailed by the outbreak of the war.

12. After the death of H. W. Vogel the Photographische Mitteilungen
were merged with the Photographische Rundschau published by W.
Knapp (the latter was originally edited by Charles Scolik in Vienna).

13. The textbooks edited by Dr. Julius Schnauss were very popular.
We cite here the most important: Schnauss, Photograph. Lexikon fur den
praktischen Photographen, Leipzig, (1st ed., i860; 3d ed., 1868); Kate-
chismus der Photographie, Leipzig (1st ed., 1861; 4th ed., 1888); Das ein-
fachste und sicherste Trockenverfahren der Gegenwart (1863), (Kollo-
diumbadeplatten mit einem Praservativ von Rosinen-Absud.); Der Licht-
druckund die Photolithographie (3d ed., 1886; 7th ed., revised by August
Albert, 1905).

14. The Geschichte der Wiener Universitat von 1848-1898 (pub. by
Alfred Holder, Vienna), issued by the Academic Senate in 1895, states

8 14 NOTES TO PAGES 688-709

that the University Institute for Physics moved in the fall of 1851 to the
House Erdberg, Hauptstrasse 104. When the streets in Vienna were
zoned differently, the house mentioned (built in 1777) was renumbered
Bezirk III, Erdbergerstrasse, No. 15. The house belonged at that time to
a citizen by the name of Kier Tuberius. According to the directory of
the city of Vienna of 1875, the subsequent owner was recorded as the
photographer Josef Lowy. It was here that the dry-plate works of J.
Lowy (d. March 24, 1902) and of J. Plener were housed and that the
first Eder orthochromatic eosine plates were produced. It was here also
that H. W. Vogel introduced his azaline plates in Vienna. Later their own
building was constructed, adjoining in the Parkgasse, in which the suc-
cessors to the Lowy firm, as Wiener Kunstdruck A.-G, Vienna III, Park-
gasse 13-15, carried on their photoengraving business.

15. Jahrb. f. Photogr. (1897), p. 263.

16. W. Exner in the Neue Freie Presse of March 21, 1928; also Phot.
Rundschau (1928), p. 195.

17. Most of the reports of the Institute were published in the Phot.
Korresp. The purely scientific research in photochemistry and spectro-
analysis by Eder and Valenta will be found in the reports of the sessions
and the memoirs of the Vienna Academy of Sciences (class for mathe-
matics and natural sciences). The collected works of J. M. Eder and E.
Valenta, Beitrdge zur Photochemie und Spektralanalyse (Vienna, 1904)
were printed and published by the institute.

18. See Wilhelm Exner, Erlebnisse (Vienna, 1929).

19. Eduard Kuchinka, “Die Sammlungen der Graphischcn Lehr- und
Versuchsanstalt in Wien,” Phot. Korresp. (1928).

20. Dr. Karl Gustav Helmer Backstrom was born September 8, 1891,
at Stockholm, where he studied physics and chemistry at the university.
He was an assistant at the technical high school there (1917-25), and
since 1929 teacher at the Royal Seminar for Female Teachers. With
Hertzberg he edited the Nordisk Tidskrift for Fotografi; since 1923 he has
written several widely circulated Swedish books on photography.

21. The statement in Jahr bitch f. Phot., (XXX, 47) that the first pho-
tographic exhibitions in Sweden took place in 1843 is a typographical
error.

22. Phot. Korresp. (1924), p. 22.

23. From Fritz Kohler, For sc her- und hist oris c he Bildnisse, 1911-
/ 928, Leipzig.

24. An illustration of the Academy of Science is in A. B. Grenville,
St. Petersburg; a Journal of Travels to and from that Capital (London,
1828).

25. See the report by A. Nadherny and Weissenberger in Phot. Korr.
(1893).

NOTES TO PAGES 710- 71 1 815

26. W. Weissenberger of Vienna reported in 1886 a method for sen-
sitizing bromosilver gelatine plates by adding a cyanide solution, decolor-
ized with acetic acid; this caused the plates to show their sensitivity to
colors only after being dried (Phot. Korresp., 1886, p. 591; and 1896,
p. 1 31). This process was taken up later again in the methods for sensi-
tizing with isocyanide, sensitive to acids (see W. Dieterle, this Hand-
buch, 1932, 111(3), I 9 I_2 4 2 , “Die Herstellung farbenempfindlichen Schich-
ten”). Weissenberger also recommended the use of chrome baths con-
taining manganese sulphate (1888); see Handbuch (1926), Vol. IV(2).

27. “The transcript of this work,” writes Plotnikow, “and the ar-
rangement of the material which it has taken years to gather was begun
in the summer of 1917 on my estate ‘Schwarzer See’ in the Department
of Riasan. All about us stormed the masses of the Russian people who
had torn themselves loose from all human and cultural ties, having been
overwhelmed by a mania for destruction. Dav after day I had to witness
powerlessly the destruction and sacking of my country property, which
I had labored with such difficulty, toil, and expense of money to bring
to its high economic standard. Finally, in November of the same year,
1 lived to see my estate leveled to the ground. The library of my country
house passed into the making of cigarette papers. In Moscow the writ-
ing of my book was continued. There, in a few wretched rooms, my
family found shelter, amid the volleys of continuous cannon and guns
of Bolshevik revolts. The frightfulness of the terrorist government which
followed was added to by the lack of food. Grievous and distressing were
the few hours left for my work. My library in Moscow, which I had col-
lected for years with such love and labor, diminished constantly under
the necessity of bartering the books in exchange for food in order to
snatch my wife and child from the danger of starvation. From the posi-
tion of professor at the university I was discharged in the first days of
the Revolution, on March 20, 1917, by the arbitrary, illegal, and violent
proceedings of the Minister of Education, Cadet Manuiloff, who toler-
ated only members of his own party. The first Russian photochemical
laboratory, which I had installed laboriously and partly from my own
funds, was also liquidated. As the problem of providing food became
more and more acute and the sources dwindled, we fled in peril of our
lives in the fall of 1918 from this socialistic paradise to relatives in
Ukraine. It was in Charkoff that the mathematical part of my Allgemeine
Photochemie (Berlin-Leipzig, 1920) was written. The bolshevist waves
of blood and hunger continued to approach, closer and closer, the rich
and beautiful Ukraine; they threatened to engulf it and to cut me off
anew from the world of culture. In the name of the new “Soziale Gerech-
tigkeit’ I was reduced to the state of an itinerant mendicant, while oth-

8 1 6 NOTES TO PAGE 712

ers, stronger physically, enriched themselves at my expense. They robbed
me even of my scientific haven. Whether fate has in store for me an-
other such opportunity, where I might continue in peace my scientific
research, is at this writing very problematical. Unfortunately scientists,
more than elsewhere, depend on the consideration of party, nationality,
and prejudice. My position was desperate. However, then came the long-
hoped-for assistance out of Germany. I am indebted to the German men
of science and industry, for through their timely intervention I was per-
mitted to spend Christmas 1918 in Leipzig with my friends and patrons.
Unfortunately, my wife and child had to be left behind in Charkoff for
two years; during that time I was unable to communicate with them,
owing to the shortsightedness and naive politics of the ‘Entente.’

“On German soil, so fertile for every scientific research, I was able
to conclude my work Allgemeine Photochemie. Thus came into being
a textbook which, I believe, contains at least sufficient material offered to
our present generation in research to make possible a further successful
development in this interesting scientific, practical, and gratifying field.

“Hunger, misery, and bitter necessity, extraordinary personal inse-
curity, often bordering on the danger of one’s life, were constant com-
panions during my hours of study.”

At the end of this dramatic statement Professor Plotnikow, who had
found a temporary position at Agfa in Berlin through the recommendation
of Professor W. Nemst and the general director, F. Oppenheim, thanks
his friends who had stood by him during this trying time of his life.

28. Dr. Janecek, bom in Prague, became first assistant to Professor
Pohl of the Technische Hochschule in Vienna, was called to Agram by
the Banus of Croatia, where he was the first professor in the 1870’s to in-
troduce a department for chemistry at the university.

29. The Russian Professor Samoilowitsch contributed numerous aero-
photographic and photogrammetric exposures taken during the voyage
of the Graf Zeppelin on its polar trip in 1931. The German scientists Dr.
Aschenbrenner (Munich), Dr. Basse (Berlin), and Dr. Gruber (Jena)
carried out the scientific cartographic results of Samoilowitsch’s photo-
graphic work ( Forschungen und Fortschritte, 1932, p. 23).

30. L. Scharlow, working in the Geologic Committee in Leningrad,
published a formula for the production of silver bromide gelatine by
precipitation of silver bromide, washing and the following emulsification
in gelatine, which results in clear, less sensitive emulsions for silver bro-
mide papers (Phot. Indust., 1924, p. 233).

31. A. Walenkov, also A. Denisoff, “Physikalisches Institut der Uni-
versitat Leningrad,” Z eitschr. f. wissensch. Phot. (1929), Vol. XXVII.

NOTES TO PAGES 712 -715 817

32. A. Kirilow, “Physikalisches Institut in Odessa,” Z eitscbr. f. wis-
sensch. Phot. (1929), Vol. XXVI.

33. N. Barascheff and B. Semejkin, Z eitschr. f. wissensch. Phot. (1930-
31), Vol. XXVIII.

34. See Jahrbuch fur Photographic (1912), p. 294.

35. See Handbuch (1930), III ( 1 ), 172, “Die Photographic mit Bromsil-
ber-und Chlorsilbergelatine,” by Eder und Liippo-Cramer, and elsewhere
in this work. Several of Burton’s works have been translated into German
(Das ABC der modernen Photo graphie, 3d ed., Diisseldorf, 1887) and
into French ( Fabrication des plaques au gelatinobromure, Paris, 1901).
Exposure Tables (1882) of W. K. Burton are reported in Handbuch (1893),
II, 263-64.

36. The intense interest taken by the Japanese in the “Photograph-
ic Salon” (1929) was best shown by the 1700 photographic entries
of which 400 took prizes (Japan Photographic Almanac, 1928-29, p. 2).
The exhibit at the “V. Internationale Photographische Salon” in Tokyo
was sent to Vienna and shown there by the “Wiener Photoklub,” in De-
cember, 1931, where it excited great interest.

37. Production statistics are published in Japanese photographic an-
nuals (1929-30), giving figures covering manufacture of photographic
merchandise made in Japan. Cameras, etc., 2,000,000 yens, plates and pa-
pers about 3,000,000 yens, against an import of photographic items
amounting to 8,000,000 yens. Important information on photographic
trade statistics in Japan are found in Phot. Chronik (1932), p. 6,

INDEX

Aarland, G., 693
Abbe, Ernst, 402, 405, 407
Abildgaard, 121, 129; “Ober die Wirkung
des Lichtes auf das rote Quecksilber-
oxyd,” 744

Abney, Sir William de Wiveleslie, 363,
43°i 434i 443i 4S4"55' 563, 781; Emulsion
Processes in Photography, 430; The
Practical Working of the Gelatine
Emulsion Process, 430
Absorption, photochemical: Grotthuss’s
law of, 166-68, 418-19
Accum, Chemische Unterhaltungen, 106
Achromatic lens, 50, 133, 251, 290, 292,
294, 298; see also Aplanatic lens
Achromatism, jo, 149-50, 251, 298
Ackerman, Carl W., George Eastman,
380, 487, 492, 786
Adams, Charles M., xiii
Adamson, Robert, 327, 349
Adelskold, C. A., 702
Aerial photography, 393-98, 401-3
Agenda Lumiere, 677, 695
Agfa Company, 432, 435, 437, 662, 695
Agricola, Georg, 24, 25
Aguado, Olympe, Count, 307, 351
Aguilonius, Franciscus, 381, 639
Air eddies, photographic study of, 525-27
Airy, G. B., 45
Aktinometer, 449
Albanus, C. F., 450

Albert, August, 549, 613, 620, 621, 628;
V erschiedene Reproduktionsverfahren
mittels lithographischen und typo-
graphischen Druckes, 61 3, 620, 804;
Die verschiedenen Methoden des Licht-
druckes, 620, 803; “Die Fehlertabellen
fur Lichtdruck,” 620; Der Lichtdruck
an der Hand- und Schnellpresse, 620;
Der Lichtdruck und die Photolitho-
graphic, 620; T echnischer Fiihrer durch
die Reproduktions-verfahren, 620, 621;
Die Reflektographie, 620
Albert, Eugen, 378-79, 595, 599, 620, 633,
654, 808; invention of isochromatic col-
lodion emulsion, 379, 467-68, 618; “On
the Change of Color Tones in Spectral
and Pigment Colors under Diminishing
Intensity of Light,” 379
Albert, Josef, 378, 618, 619, 620, 646, 647
Albert, Karl, 522, 597, 620, 710; Lexicon

der graphischen Techniken, 620, 647,
660

Albertus Magnus, 23, 57; Compositum de
compositis, 24; De mineralibus mundi,
733

Albinos, 126

Albumen: use on glass negatives, 339-41;
use on collodion plates, 372-73, 375;
print paper prepared with, 535, 536, 781,
792; use in photolithography, 609, 610,
61 1

Alchemic medals, see Medals, Alchemic
Alchemists, 15-33; production of silver
chloride by wet process, 27-29; study of
phosphorescence by, 57-60
“Alcmaon,” epithet bestowed on J. H.

Schulze, 72-73
Algraphy, 615-16, 803
A1 Husen (lbn al Haitam), 1
Alinari, Arturo, 701

Allgemeine Gesellschaft fur Anilin Fabri-
kation, see Agfa Company
Allon, 394

Almeida, Joseph Charles d’, 383, 648, 772;
“Nouvelle appareil stereoscopique,”
77*

Alpha papers, 448

Alpine photography, see Mountain pho-
tography

Alsace Printing Machinery Co., 606
Aluminum: use for lithographic printing,
615-16, 803; use in collotypy, 621
Amboise, Cardinal Georges d’, 204, 207
America, see United States
Amici, 290

Ammonia: use in developers, 376; emul-
sions ripened with, 425, 428-31
Ammonium oxalate, mixed with mer-
curic chloride: light-sensitivity of, 164-

Amphitype process, 339
Anastigmatic lens, 407-10, 775, 776
Andemaos, 343

Andraud, Une Derniere Annexe au Palais
d'lndustrie, 393
Andree, S. A., 396

Andresen, Momme, 432, 434-35, 437-38,
551; “Zur Aktinometrie des Sonnen-
lichtes,” 435; Das latente Lichtbild, 435;
Agfa-Photo-Handbuch, 435; “Enrwick-
ler-Substanzcn,” 435

820

INDEX

Angerer, Carl, 623-26, 632, 804
Angerer, Ludwig, 304, 303, 306, 352, 353
Angerer, Victor, 353, 431, 445, 598, 599,
801

Angerer & Goschl, 625, 631, 633, 653, 654,
804

An^lada, 173

Animal locomotion: photographed by
Muybridge, joi-j; photographed by
Marey, J07

Anschutz, Ottomar, 409, 512-13, 789
Ansco Company, 447, 493, 494
Antiplanat lens, 407
Anthony, 375

Anthony and Scovill Company, 490
Antilux, 724

Aplanatic lens, 403-7, 408
Aqua fortis, see Nitric acid
Aqua rubi, 17

Aquatint grain, 591, 594, 595, 596, 600, 799
Arago, Francois jean, 2J-26, 137, 202, 243,
259, 270, 334-35, 398; report on daguer-
reotypy to French Academy of Scien-
ces, 140, 141, 130, 245, 252, 287, 310-11,
756; report on daguerreotypy to French
Chamber of Deputies, 232-41, 242, 258,
385; “La Daguerreotypie,” 252
Archaeology, benefits of daguerreotypy
to, 234

Archer, Frederick Scott, 299, 345-47, 362,
363, 768

Archertype, 346
Argentotype process, 543
Aristo papers, 448, 536, 538
Aristostigmat lens, 409, 41 1
Aristotle, 1, 2, 3, 36, 57, 729; views on
color, 3-4, 10; Metaphysik, 729
Armat, Thomas, 719
Armstrong, T. N., 533
Arndt and Troost, 543
Arons, Leon, 533
Arrowsmith, Charles, 209
Arsenic disulphide, light-sensitivity of, 142
Arsenic sulphide, light-sensitivity of, 146
Artigue, Victor, 560

Art Photographic Company, Limited, 602
Arts, relat on of photography to, 235,
2 4 2 ‘43. 3 '4. 348-51.

Arts, graphic: contribution of early pho-
tographic inventions to, 331-33
Artus, 730

Artus, Willibald, 177
Asahiphoto Industrial Co., Ltd., 71 j
Aschenbrenner, Dr., 816
Ashman, 538
Ashton, 587

Asphalt, light-sensitivity of, 103

Asphaltum process, 61 1; use by Niepce,
197, 199-203, 204, 206, 207, 218-23, 2 5°>
608; improvement by Niepce de Saint-
Victor, 591-92 ; use in photolithography,
608

Asser, Eduard Isaak, 612, 703
Association Beige de Photographie, 703
Association du Musee des Photographies
Documentaires, 698
Astigmatism, 45

Astrology, speculations of alchemists in,
ij-21

Astronomical photography, 269-70, 584,
798

Astronomy, value of daguerreotypy to,
2 37

Atelier des Photographer!, 474

Atmography, discovery of, 268, 338

Attout, 468, 469

Aubel, Carl, 613

Aubel & Kaiser, 613

Aubree, 529

Auer, Alois (von Welsbach), 36, 568-73,
575, 693; “Disputes about the Owner-
ship of New Inventions,” 569; Die
Entdeckung des Naturselbstdruckes,$(x)\
Geschichte der HofundStaatsdruckerei,
571; Das typometrische System in alien
seinen Buchstabengrossen, 571; Mein
Dienstleben, 572; Das Benehmen eines
jungen Englanders, 796
Auerbach, Felix, Ernst Abbe, 408
Auer von Welsbach, Carl, 533, 572, 573,
7 2 4. 797

Aufermann, 638

Aussig Chemical Society, 481, 484
Austria: early interest in daguerreotypy
in, 245, 246-48, 280-84; photography in,
ix, 680-92, 694

Autochrome process, 661-62, 672, 809
Automats, photographic (so-called), 371
Automats, printing, 441, 445
Autopolygraph, 358

Autotypie, 626, 629, 630-31, 805; see also
Halftone process
Averroes (Ibn Ruschd), 2
Aviar lens, 411
Avicenna, 1
Axmann, Jos., 577
Azaline plates, 460-61, 468, 784

Bache, Alexander Dallas, 288
Bachrach, D., 538

Backstrom, Helmer, xi, 214, 283, 287, 337,
701, 702, 814

Bacon, Francis (Baron Verulam), 125;
Sylva sylvarum, 125

INDEX

821

Bacon, Roger, 2, 28, 29, 31, 37, 38, 733, 734
Baden-Powell, Lt., 397
Baden-Pritchard, Captain, 447, 599
Baekeland, Leo, 446, 780
Baeyer, Adolph von, 484
Baker, Thome, 662
Balagny, G., 485, jio
Balard, Antoine Jerome, 172, 173
Balduin, Christoph Adolph (Baldewein),
30; study of phosphorescence by, 57-60,
61, 73i 7371 Miscellanea curiosa medico -
pbysica Academiae naturae curiosorum,
58; Aurum superius et inferius aurae
superioris et inferioris hermeticum et
phosphorus hermeticus , 737
Baldus, 576, 592, 622
Ballistic photographs, 524-27
Balloon photography, 393-98; see also
Aerial photography
Bamberg, Karl, 776
Barascheff, N., 817

Barbaro, Daniel, 734; La prattica della
perspettiva, 42
Barbier, H., 477
Barbieri, 705

Barium sulphide, luminosity of, 57; see
also Bologna stone
Barker, Robert, 209
Barr, Captain, 331

Barreswil and Davanne, 608, 609; Chimie
photographique, 360, 361; Die Anwen-
dung der Chemie auf die Photographie,
802

Basilius Valentinus (pseudonym), 27-29,
733; Ein kurtz sumnarischer Tractat
Fratris Basilii Valent ini des Bene dieter
Ordens, von dem grossen Stein der
Uralten, 27; Von den natiirlich und
obernatiirlichen Dingen, 27; De occulta
Philosophia, 27; Haliographia, 27;
Triumph-W agen Antimonii Basilii Val-
entini 27; Das letzte Testament des
Basilius Valentinus, 28; Chymischen
Schriften des Basilius Valentinus, 28
Basse, Dr., 816

Batut, A., 396, 397; La Photographie
aerienne par cerf-volant, 774
Baudin, 342

Bauer, Alexander, 20; Die Adelsdokumente
osterreichischer Alchimisten, 21, 732;
Wiener numismatische Zeitschrift, 732;
Chemie und Alchimie in Osterreich,
732; Humphry Davy, 745
Bauer, Francis, 198, 206, 207
Bauerle, Adolf, 287

Bavarian Government Institute for Photo-
graphic Procedure (Munich), 693

Bayard, Hyppolite, 334, 335, 368
Beale, 500

Beard, 280, 315, 355
Beauregard, Testud de, 556, 810
Beautemps-Beaupre, 398
Beauviere, 580

Beccarius (Giacomo Battista Beccaria),
62, 86-87, 89, 93, 98; light-sensitivity of
silver chloride discovered by, 86-88, 93,
140; Treatise on Artificial Electricity,
87; “De vi quam ipsa per se lux habet,”
(with Bonzius), 738
Becher, Chymische Concordanz, 732
Beck, Viennese daguerreotypist, 281
Becquerel, Antoine Henry, 2O5
Becquerel, Edmond, 264-65, 267-68, 367,
552; La Lumiere, ses causes et ses effets,
vi, 26, 265, 266; studies action of red rays
of spectrum (Becquerel phenomena),
265-66, 355, 758; discovers sensitizing
effect of chlorophyll at red end of spec-
trum, 460, 465, 645, 652, 807; investiga-
tions in photochromy, 664-65, 667
Becquerel phenomena, 265-66, 355, 758
Bedrijfsphotographie, 703
Beechey, Canon, 378
Beemeter, 449
Beer, 284
Begelow, 342, 343
Belgium, photography in, 703
Bellini, 377

Belloc, 346; Traite . . . de la photographie
sur collodion, 360; Photographie ra-
tionale, 360; Les Quatre Branches de
la photographie, 360, 768
Benedetti, Giovanni Battista, 42
Benediktbeurener lens, 308, 763
Bennet, Charles, “A Sensitive Process,” 426
Bennetto, 658
Bentiviglio, Conte, 325
Benzelstiema, Lieutenant, 287
Berard, 185

Berberine yellow, 752; light-sensitivity of,
189

Berchtold, M., 626

Beretninger fradansk fotografisk Foren-
ing, 704

Bergman, Torbern Olof, 95, 96; De acido
sac chari, 95; Opuscula pbysica et
chemica, 95, 739
Bergstrom, j. W., 287
Berkeley, Herbert Bowyer, 433, 545
Berlin Photographic Society, 683
Berliner deutsche Photographen Verein,
684

Bermpohl, 475
Bernaert, 428

822

INDEX

Bernard, 660

Berres, Josef, 386, 528, 577, 578, 580; Ana-
tomic der mikroskopischen Gebilde des
menschlichen Korpes, 386; Phototyp
nacb der Erfindung des Professors
Berres in Wien, 333, 577
Berry, Miles, 251
Berthier, H., 383, 384
Berthollet, Comte Claude Louis, 107-9, !I 4>
143-44; experiments with silver chloride,
101, 109, 143-44, 158, 160, 161, 162; ex-
periments with chlorine water, 107-9,
112, 1 14, 152, 413, 742; De I’influence de
la lumiere, 108; Elements de Part de la
teinture, 1 14; Essai de statique chimique,
143, 741 ; Histoire de PAcademie royale
des sciences, 741

Berthollet, M., Die Chemie im Altertum
und Mittel alter , 733
Berthon, 672
Bertillon, Alphonse, 441
Bertrand, Recueil des travaux scientifiques
de Leon de Foucault (with Gabriel),
773

Bertsch, 387, 393
Berzelius, 167, 168, 176, 190, 420
Bestuscheff, Count, 56, ioi, 707
Bevan, 551

Bezzenberger, “Ein angeblicher Vorgang-
er Daguerres,” 182

Bichloride of mercury, light-sensitivity
, of ' ‘43

Bichromates, light-sensitivity of, 178-79
Bielicke, 41 1

Bindheim, 109; Chemische Annalen, 741
Bingham, Robert J., 307, 346; Photogenic
Manipulation, 346; “On the use of Col-
lodion in Photography,” 346; Instruc-
tion in the Art of Photography, 360
Binocular vision, 45-46
Biograph, 522

Biondo, M. A. B., Traktat von der hoch -
edlen Malerei, 85
Bio-phantascope, 515, 5 17
Biot, John Baptiste, 278, 320, 334, 534, 756
Biotar lens, 298
Birckbeck, 54
Bird, P. H., 329

Bischoff, J., 88-89; Versuche einer Ge-
schichte der Fdrbekunst, 10, 89
Bishop, Joaquim, 288
Bisson, August, 359
Black, J. W., 394, 395
Blacklock, H. H., xi
Blair Camera Company, 490
Blanchere, de la, see La Blanchere, de
Blanquart-Evrard, 327-29, 332, 339, 392,

535, 646, 792; Album photographique de
P artiste et de P amateur (with Focke-
day), Hi-, La Photographic, ses origines,
ses progres . . . , 360, 754, 766, 792; Proce-
des employes pour obtenir les epreuves
de phot, sur papier, 765; Traite de pho-
tographic sur papier, 765
Bleaching, 187-92; early theories on causes
of, 5j, 85, 86, ioo, 740; Saussure studies
action of light on colored materials,
1 12-13; Berthollet discovers bleaching
with chlorine, 1 14, 742; development of
photographic bleaching-out process, 1 59,
168, 263, 673-75, 748, 749
Blecher, Karl, 638
Blechinger, 801

Blechinger and Leykauf, 353, 599, 801
Bloch, Elsa, 249

Block, Olaf, "Development in Infra-red
Photography,” 781
Blow, T. B., 714

Blue glass, use in photography, 355-56
Blueprints, 549
Blumenbach, 125

Boccone, Silvio, “Disegni nacurali et ori-
ginali,” 35

Bock, Emil, Die Brille und ihre Geschich-
te, 2

Bockmann, 116, 121, 136, 158; Versuche
uber das Verhalten des Phosphors. .
743. 744

Bodenstein, Max, 419, 777; Flundert Jahre
Kunstgeschichte Wiens in den Reges-
ten, 798

Bogisch, A., 435, 780
Bois-Reymond, Dr. R. du, 648, 789
Bollmann, 560
Bologna stone, 57, 58, 60
Bollstadt, Count Albert von, see Albertus
Magnus

Bolton, W. B., 377, 378, 425, 771
Bombay, Journal of the Photographic
Society of, 679
Bonacini, Carlo, 699
Bond, George Phillips, 457
Bond, W. C., 270

Bone, Homberg’s experiments with, 31, 92
Bonzius, 87, 88, 89, 93, 100; “De vi quam
ipsa per se lux habet...” (with Bec-
carius), 738

Boston Camera Co., 490
Bottger, 342,617

Bottiger, ldeen zur Archaologie der
Malerei, 730
Botton, Captain, 791

Boullay, Pierre Francois Guillaume, 143,
164. 745

INDEX

Boulton, Matthew, ioo, 1 34, 135
Bouly, Leon, jii, 790
Bourfield and Rouch, 357
Boussingault, Jean, 187
Boussod and Valadon, 588, 599, 635, 801
Bouton, Charles Maria, 209, 210, 214, 734
Boutron-Chalard, A. F., 190
Boyle, Robert, 29; Experiments and Con-
siderations upon Colours, 30, 67; The
Systematic Cosmos, 44
Braconnot, Henry, 178, 330, 342
Bradbury, Henry, 796
Bradford, L. H., 611
Brady, Matthew B., 339
Brand, 59

Brandau, Universal Medicine, 18
Brande, W. T., Chemistry, 757
Brandenburg, Friedrich, 165, 707
Brandes, Rudolf, 171, 174, 528
Brandlmeyer, G., 654, 656
Brandner, 383

Brandweiner, Adolf, 601-2, 603, 604, 605,
801

Brasseur, 661

Brauer, L., Die Forschungsinstitute, ihre
Geschichte, Organisation und Ziele, 694
Braun, Adolph, 466, 558, 559
Braun, Gaston, viii, 466-67, 588, 599, 708
Breath pictures (Hauchbilder), 260
Brebisson, de, 339, 533
Breeman, L., 516
Brengou, Henri, 549

Brewster, Sir David, 271, 349, 381, 382, 640,
679; Optics, 157; The Stereoscope, 735,
772; Introd. ad. philos. natur., 807
Breyer, Albrecht, 336, 337, 767
Breyertypes, 336-37
Breysing, 209

British Cartographic Institute, 694
British Journal of Photography, 336, 679
British Journal Phot. Almanac, 678, 679
Bromeis, 617

Bromides, use in wet collodion process, 361
Bromine: discovery of, 172-173; sensi-
tivity of daguerreotype plates increased
with addition of, 265, 275-78
Bromoil process, 564-65, 607-8, 780, 801
Bromo-iodide, light-sensitivity of, 276
Brongniart, 262

Brooker, “Recent Advances in Sensitizers
for the Photography of the Infra-red”
(with Hamer and Mees), 781
Brothers, 530, 531
Brown, A. B., 500

Brown, George E., viii, xiii, 249; “The
Last Days of Daguerre . . . 756
Brownell, Frank A., 490

823

Brownie camera, 491
Brucke, E., 125

Bruckmann A.-G., F., 599, 602, 604
Brugnatelli, Luigi Gasparo, 166
Brunner & Co., 630
Buchholz, 120, 146, 157, 160, 161
Buchner, Eduard, 258
Buchner, Johann Andreas, 166, 189; Re-
portium fur die Pharmacie, 187, 749,
75 °. 75 *

Biihler, Atelier und Apparat des Photo-
graphen, 355
Bull, Lucien, 526

Bulletin beige de photographie, 703
Bulletin de F Association beige de photo-
graphie, 703
Bullock, Edward, 626
Bullock, James, 626
Bullock, Lothrop L., 615
Biilow, Leonhard, 304
Bunsen, Robert Wilhelm, 152, 412-16, 449,
450, 452, 529, 530, 532; “Photochemische
Untersuchungen” (with Roscoe), 413
Bunzli and Continsouza, 522
Buonvicino, 116

Burger, Wilhelm, 374, 686, 687, 688
Burgess, George K., 694
Burgess, John, 424, 440; The Argentic
Gelatino-Bromide Worker’s Guide, 430,
440

Burkhardt, E. G., 177; “Ober Verbindun-
gen der Quecksilberoxyde mit organ-
ischen Sauren,” 751
Burnett, J. C., S3 7, 626, 767
Burns, Dr. 694

Burton, W. K., 714; Das ABC der modem-
en Photographie, 817; Fabrication des
plaques au gelatinobromure, 817
Busch, Emil, 270, 304-6, 307, 365, 409, 41 1,
695

Busch, Georg, 45
Buss, Otto, 537
Butler, 658

Biixenstein, Georg, 464, 654

Cadett, 445
Cady, Parker B., 490
Caesariano, Caesare, 38, 734
Caille, E. C. G., 662

Calotype process, 3 ' 7 . 3 22 . 30 . 3 2 7 . 3 2 9 .

348, 349, 764; see also Talbotypes
Camarsac, Lafon de, 566; Application de
I’heliographie aux arts ceramiques aux
emaux, 796; Portraits photographiques
sur email, 796

Camera: invention of photography in, by
Niepce, 193, 195, 197-98, 200-3, 2 5°;

INDEX

824

Camera ( Continued )
commercial introduction by Daguerre
and Giroux. 250-56, 756
Camera, De, Amsterdam, 703
Camera, Luzerne, 705
Camera obscura: 36-45, 272-73, 734, 755;
described by Leonardo da Vinci, 38-40;
described by Porta, 40-41; experiments
by Wedgwood and Davy with, 137, 318;
used by Niepce, 198, 220, 234; used by
Daguerre, 214, 250; used by Talbot,
317 . 319

Cameras, enlarging, 391-93; see also En-
largements

Cameras, pistol, 358, 770
Cameras, portable, first mention of, 43
Cameras, three-color, 657-58
Cameron, Mrs. Julia Margaret, 350
Camp, Maxime du, 332; Souvenirs et
pay sages d’Orient, 332
Campbell, Life of Maxwell (with Gar-
nett), 807
Campbell, W., 789
Campeel, 147

Capstaff, J. G., 491, 660, 809; “The Koda-
color Process for Amateur Color
Cinematography” (with Seymour), 811
Carbon, use in photographic printing,
554-59. 566-67
Carbonell, 177
Carbon perchloride, 171
Carbro prints, 562
Carbutt, John, 486

Cardano, Girolamo, De subtilitate, 40
Carpenter, 387
Carpentier, 519

Carrier pigeons, photomicrographs sent
by, 389-90
Carry, 54

Cartes-de-visite, see Visiting card portraits
Casaseca, J. L. 174
Casciorolo, 57
Casler, 522
Casoidin papers, 537
Castel, 85-86; Die auf lauter Erfahrungen
gegriindete Farbenoptik, 85
Catalysotype, 326
Caustic stone, 23
Cavetou, 165

Celestial photography, see Astronomical
photography

Cellio, Marco Antonio, 45
Cellofix papers, 538
Celloidin papers, 347, 536
Celluloid, used as film base, 485-86, 489-
9‘, 49 2 ~93

Cellulose, 342, 343-44

Cennini, Cennino, Bucb von der Kunst;

oder, Traktat der Malerei, 85
Cerargyrite, see Homsilver
Chalkotype, 637
Chapman, 776

Chaptal, Jean Antoine Claude, no, hi,
730, 742; “Observations sur l’influence
de Pair et de la lumiere dans la vegeta-
tion des sels,” 742

Chardon, 378; Pbotographie par emulsion
sensible . . . , 430

Charles, Jacques Alexandre Cesar, 141, 142
Charlieu, Millet de, 249
Chauveau, 509

Chemical rays, 131, 146-47, 149-50, 157;

see also Solar spectrum
Chemicals, photographic, sale of, 347
Chemigraphy, 624
Chemitypy, 804

Chevalier, optical firm of Paris, 198-99,
207-8, 290; lenses constructed by, 279,
289, 290, 291, 295, 298, 310
Chevalier, Charles Louis, 132, 207-8, 214,
251, 253, 255, 294-96, 299, 386; Sur une
modification apporte cm doublet de
Wollaston, 208; Nouvelles instructions
sur Vusage du daguerreotype, 208; Me-
langes photographiques, 208; Sur quel-
ques modifications apportees a des in-
struments optiques, 208; Pbotographie
sur papier, verre et metal, 208; Metbodes
photographiques perfectionnees, 208;
competition with Voigtlander over
lenses, 294-96; Pbotographie sur papier
sec, collodion . . . , 360
Chevalier, Jacques Louis Vincent, 207, 208
Chevalier, Louis Marie Arthur: Met bode
des portraits des grandeur naturelle et
des agrandissements photographiques,
208; Etude sur la vie et les travaux scien-
tifiques de Charles Chevalier, 208
Chevreul, Michel Eugene, 131, 190, 192
Chevrier, 204
Childe, 53

Chimenti, Jacopo, 46, 381
Chisholm, 135
Chistoni, C., 742

Chlorine, increased sensitivity of daguer-
reotype plates by use of, 276-78, 665
Chlorine detonating gas, light-sensitivity
of, 151-53, 155, 4D. 777. .

Chlorine water, light-sensitivity of, 107-9,
1 1 2, 152, 412
Choiselat, 260, 261
Choreutoscope, 500
Christensen, F. J., 541
Christman, Leon, 776

INDEX

Chromates: light-sensitivity of, 179, 552-
54, 559> 593 ; photographic processes
with, 552-59, 793; Poitevin introduces
photography with, 553-57; Eder studies
chemical reactions of, 559; use in photo-
ceramics, 567

Chromium, discovery of, 1 19
Chromometer, 649
Chromoscope cameras, 646, 649, 658
Chronographs, 502, 504, 507, 508, 510
Chronophotography, 504, 507, 510, 511,
516, 520

Chrysotype, 264

Ciamician, Giacomo, 699; “Azioni chim-
iche della luce,” 699; “Photochemistry
of the Future,” 699
Ciceri, 754
Cine-Kodak, 673
Cinema, origin of term, 790
Cinematograph, ballistic, 526-27
Cinematography: forerunners of, 495-500,
501-5, 506-13; controversy over inven-
tion of, 509-12; development of, 514-24,
7 I 7~ I 9

Cineopse, Le, 789
Cinnabar, effect of light on, 6-8
Citric acid, 119
Civiale, Aime, 358

Civil War, American: Matthew Brady’s
photographs of, 359; balloon photog-
raphy used in, 394-95
Clark, Walter, xiii, 450, 491, 696
Clauder, G., “Treatise on the Philoso-
pher’s Stone,” 15

Claudet, A. J. F., 251-52, 280, 298, 314, 449,
578; studies action of spectrum on da-
guerreotype plates, 263, 267; investi-
gates use of bromo-iodide and iodo-
chloride in daguerreotypy, 276, 278, 760;
uses painted backgrounds in daguerreo-
type studio, 356, 769; Le Stereoscope,
383; Recherches sur la theorie des prin-
cipaux pbenomenes de photographie,
762; Nouvelles recherches sur la differ-
ence entre les foyers visuels et photo-
genique, 762

Claudet and Houghton, 356
Clay, Reginald S., 41 1
Clement, 163

Clerc,Louis-Philippe, xiii, 383,638,677,812;

La Technique photographique, 549
Cleve, C. W. Scheele ett minnesblad
pa hundrade ardsdogen of bans dod,
739

Clorona papers, 448
Cochineal papers, 182
Coindet, Dr., 164

825

Coissac, G. M., Histoire du cinemato-
graphe, 523

Cole, William, 11-12; “Observations on
the Purple Fish,” 730
Coleridge, Samuel Taylor, 135
Collen, Henry, 642
Collinear lens, 410
Collodion emulsions, 376-79
Collodion process, dry, 372-76, 382, 395
Collodion process, wet: 326, 341; early
history of, 342-47; theory and practice
of, 357-69; disadvantages of, 357-59;
early books on, 360; intensification
methods used in, 363-66; photography
of solar spectrum by, 366-67; direct
positives in camera with, 369-71
Collotypes, 554, 563, 617-21; three-color,
646-47, 654; four-color, 653
Colomb, 791

Color photography, see Photography,
three-color

Colors: Aristotle’s views on, 3-4; used by
ancients, 6-8, 730; action of light on,
13, 85-89, 100, 1 1 2-1 3, 129, 149, 153-55,
187, 740; fastness of organic, 120;
Goethe’s studies on, 153-55; theories of
rimary, 639-41, 746; see also Light;
olar spectrum
Color sensitizers, 459, 460, 465-78, 480,
482-83, 645, 646, 647, 783, 815; see also
Desensitizing

Colson, R., Memoires originaux des Crea-
teurs de la photographie, vii, 27, 754
Comptes rendus de I’Academie de sciences,
676

Conduche, Ernst, 610
Contcssa-Ncttcl, 41 1
Cooke lens, 411
Cooper, 54
Cooper-Hewitt, 533

Copper plates, 262; Niepce’s use of, 205;

photoetchings on, 593-94, 595, 598
Copyrights for photographs, 463
Cornelius, Robert, 272, 274, 275, 288, 289
Corriere Fotografico, II, 700
Corti, Count Egon, 318
Corti, Count Hugo, 318
Corvinus, Andr. Albr., 64, 65, 72
Cotton, colloidion, see Collodion process
Courtois, Bernhard, 162, 163, 173
Cowan, 445
Coxwell, 395
Crabtree, J. 1 ., 491, 540
Cramer, Liippo Hinricus, see Luppo-
Cramer

Cranz, C., 526, 527
Creiling, 53

8z6

INDEX

Crell, Die neuesten Entdeckungen in der
Cbemie, 741
Cremiere, L., 592
Croft, W. C., 516

Crollius, (Oswald Croll) 28; Basilica
chymica, 29, 733

Cromer, G., 697, 753, 754; Revue fran-
faise de photographic, 255
Cronenberg, W., 685; Praxis der amer-
ikanischen Photogravure, 685
Crookes, William, 264, 366, 367, 457, 530
Cros, A. H., 649

Cros, Charles (Emile Gauthier, pseud.),
465, 466, 642, 643, 648-652, 656; “Solu-
tion du probleme de la photographie
des couleurs,” 649; Le Collier de griffes,
6jo; Solution generate du problbne de
la photographie des couleurs, 650; Note
yur Paction des differentes lumieres
colorees, 650
Cross, 551

Cruickshank, W., 151
Crum, 343

Crusius, C. G. Baumgarten, De Georgii
Fabricii vita et scriptis, 26
Crystalli Dianae, 23
Crystallization, 147
Cundell, 298, 328, 583
Cuprotypes, 637
Curie, Marie, 265
Curie, Pierre, 265
Cussel, 206

Cutting, J. A., 61 1 ; patent with Turner,
361

Cyanometer, 11 2
Cyanotype, 178, 542, 549

Dagherotipo, II, 679
Dagon lens, 410
Dagron, 388, 389, 390
Daguerre, Eulalia (Madame Courtin), 248
Daguerre, Louis Jacques Mande, 209-15,
*33-54. *7*-73. *79‘8o, 534; use of
iodized silver plates by, 139, 164, 223-26,
250, 253, 261-62, 269, 271; use of fixatives
by, 170, 176, 250, 254; invention of da-
guerreotype process by, 181-82, 193, 203,
250; agreement with Nicephore Niepce,
199, 215-17, 233; meeting with Niepce,
205, 207-8, 215; description of diorama
invented by, 209-14; Historique et de-
scription des procedes du daguerreo-
type et du diorama, 218, 252, 755; con-
tracts with Isidore Niepce, 226-29, *33;
use of mercury vapors for development,
227-28, 250, 253, 325; sale of invention
to French government, 230-32, 245;

manufacture of cameras with Giroux,
250-51; Geschichte und Beschreibung
des Verfahrens der Dagueneotypie und
des Dioramas, 755
Daguerreian Journal, 340, 679, 813
Daguerreotype, The, 679
Daguerreotypes: first portraits with, 271-
77; coloring of, 315-16; spectral sen-
sitivity of, 439; etching of, 577-80, 591;
historical collections of, 764
Daguerreotypy, 193, 253; sale of invention
to French government, 230-32, 245;
Arago’s report on invention to French
Chamber of Deputies, 232-41; Gay-
Lussac's report on invention to French
Chamber of Peers, 241-45; publication
of processes used in, 245, 252; carica-
tures about, 256-57; theories on chemical
basis of, 259-68; early exploitation of,
279-89; as a profession, 313-15; disadvan-
tages of, 316; displaced by wet collodion
process, 341, 346; relation to arts, 348;
used in stereoscopic photography, 382
Dahlstrom, C. A., 214
Daily Graphic (New York), 627-28, 629-
3.°

Daimer, Jos., 692
Dale, W., 396

Dallas, Campbell Duncan, 582, 583, 584
Dallmeyer, John Henry, 307, 406, 410, 474
Dallmeyer, Thomas Rudolf, 406
Dancer, John Benjamin, 299, 347, 387, 388,
389

Danesi, 701
Daniel, L., 549

Dansk fotografisk Forening, 704
Dansk fotografisk Tidskrift, 704
Darkrooms, portable, 357-59
Darmstadter, Ludwig, Handbucb zur
Geschichte der Naturvsissenschaften
und der Technik, 25, 781
Darwin, Erasmus, 100, 135
Daumier, Honore, 394
Davanne, Alphonse, viii, 368, 651, 652, 792;
Chimie photographique (with Barres-
wil), 360, 361; Recherches theoriques et
pratiques stir la formation des epreuves
photographiques positives (with Gi-
rard), 538; Nicephore Niepce, 755; La
Photographie, 792; Die Anwendung der
Cbemie auf die Photographie (with
Barreswil), 802
Davidson, W. W. L., 660
Da Vinci, see Leonardo da Vinci
Davis, Raymond, 694
Davy, Sir Humphry, 136-42, 730, 745; as
forerunner of photography with Wedg-

INDEX

wood, 63, 107, 140, 318-19, 745-46; col-
laboration with Wedgwood, 92, 136-42,
203; studies chemical action of light,
120, IJ7, 158, 167; “An Account of a
Method of Copying Paintings upon
Glass and of Making Profiles by the
Agency of light” (with Wedgwood),
136-38; produces enlarged images with
solar microscope, 139, 140, 391; experi-
ments with silver iodide, 139, 163-64;
Elements of Chemical Philosophy, 1 58;
“Some Experiments and Observations
on a New Substance Which Becomes
a Violet Coloured Gas by Heat,” 163;
“An Essay on Heat, Light and the Com-
binations of Light,” 744
Dawson, George, 686; A Dictionary of
Photography (with Sutton), 765, 770
Decalcography, 623
Decaut, 522

Dechales, Claude Francois Milliet, 49,
52; Cursus seu mundus matbematicus,
49

Decoudin, 449
Decourdemanche, 187
Dedekind, Alexander, 9, 10, 11; Ein Bei-
trag zur Purpurkunde, 10, 13; La Pour-
pre verte, 730, 731
Defregger, Robert, 638
Degotti, 209, 754
Delamarre, 529
Delaroche, Paul, 235, 348
Delessert, Benjamin, 592, 813
Delessert, Edouard, 307, 351
Della Rovere, 286
De Lucs, see Lucs, de
Demachy, Robert, 560, 561, 563, 565
Demaria, Jules, viii
Dembour, A., 804
Demeny, George, 508, 512, 516
Democritus, 1
Denier, H„ 707

Dcnisoff, A., “Physikalisches Institut der
Universitat Leningrad” (with Walen-
kov), 816
Denisse, 397

Denmark, photography in, 703-4
Density, laws of: for photographic plates,
454-56

De Roth, Fortschritte der Photogr., 810

Desbarats, George E., 627

Descartes, 50

Descamps, Palmer, 428

Desensitizing, 478-84

Desmarets, 395, 396

Desmortiers, 130, 131, 146; Recherches

827

sur la decoloration spontanee du bleu
de Prusse, 745
Dosormes, 163
Desprats, Abbe, 373
Desprets, 334

Deutsche Gelatinefabrik A. G., 695
Deutsche I. G. Farbenindustrie A.-G., 695
Deutsche Mertensgesellschaft, 606
Deutsche Photographische Gesellschaft,
684

Developers, 219, 432-36; Daguerre’s use of
mercury vapor, 227-28, 250, 253, 325;
gallic acid, 322, 327-30, 339 340, 341;
iron sulphate, 325-26, 347, 362; pyro-
gallic acid, 330, 347, 375; alkaline, 375-
76. 434. 75°i Pyrogallol, 375-76, 432-33,
436; iron oxalate, 433-34; organic, 434-
36, 444-45, 478

Development: physical, 330, 368, 375, 432;
chemical, 376, 432, 443-45; stand, 400;
with use of desensitizers in light, 478-79,
484

Deville, E., 634; “Theory of the Screen
in the Photomechanical Process,” 634
Diachromy, 540
Dialytic photographic lens, 300
Diamond, 810

Diaphanometer, invented by Saussure, 1 1 3
Diaphragms, 298-99; Niepce’s construc-
tion of iris, 198, 299
Diapositives, 443-45, 540-42
Diazo compounds, use in producing diazo-
tvpes, 550-51
Dickson, K. L., 490
Didier, L., 649

Dierbach, Beitrdge zur Kenntnis des Z u-
standes der Pharmazie, 731
Dietzler, construction of lenses by, 300-
3°3. 3°4. 3°7. 76*

Dioptrics, 302

Diorama, 209-14; invented by Daguerre,
209-1 1 ; Lewald’s impressions of Da-
guerre’s, 211-14; spread from Paris to
other countries, 214; sale of process to
French government, 231
Dioscorides, De materia medica, 8
Direct positives in the camera, 369-71
Disderi, Andre Adolphe Eugene, 307, 325,
350, 352, 355, 356, 392; Manuel opera-
toire de photographic, 351, 360; Ren-
seignements photogr aphiques, 351 ; L’Art
de la photographic, 351, 360, 769; Die
Photographic als bildende Kuvst, 769
Disderi & Co., 588

Disks, stroboscopic, 496, 497, 498, 504,
507, S"3. 787-88

8z8

INDEX

Disselhorst, Rudolf, “Das biologische
Lebenswerk des Leonardo da Vincis,”
734

Dissolving views, 53, 499
Distillation, sun, 16-17
Dixon, Henry, 377
Dixon, Joseph, 610

Dize, in, “Sur la cristallisation des sels
par Taction de la lumiere,” 742
Dobbelin & Remele, 305
Dobler, Ludwig, 499
Doctor: use in photogravure printing,
594, 596, 600-2, 605, 801 ; origin of term,
801

Doebereiner, Johann Wolfgang, 160, 172,
177, 178, 186. 542; Pneumatischen

Cbemie, 172; Z ur chemischen Kennt-
nis der Imponderabilien in der anorgan-
ischen Natur, 177
Dogmar lens, 412

Dolezal, Ed., 396, 399, 400, 401, 402; “Th.
Scheimpflug,” 402; Die Anwendung
der Pbotograpbie in der praktischen
Messkunst, 774; Die Pbotograpbie und
Pbotogrammetrie, 775
Dollond, John, 50, 251
Dominis, Antonius de, De radiis vhus et
lucis in vitris perspective et iride, 639
Domonte, Flores, 342, 343
Donisthorpe, Wordsworth, 516, 649
Donne, Alfred, 54, 259, 260, 385, 386, 577,
57^1 773; Cours de microscopie com-
plete. d’etudes medic, suivi d’un atlas,
386; Atlas d'anatomie microscopique
(with Foucault), 387

Donner, Cber die antiken Wandmalereien
in techniscber Beziebung, 730
Dorel, F., 549
Dorel, J., 549
Dorffel, T., 285
Dorpat telescopic lens, 308
Dorthes, 1 1 1 , 742

Dost, Wilhelm, 697; Vorldufer der Pbo-
tograpbie, xi, 699; Die Daguerreotypie
in Berlin 1839 bis i860 (with Stenger),
284-85; Geschichte der Kinemato-
grapbie, 697

Double-anastigmat lens, 410, 776
Douglas, G., 793
Douglasgraph process, 550, 793
Dove, Heinrich Wilhelm, 452
Doyen, 383
Drac, K. J., 649
Draper, Henry, 270

Draper, John William, no, 166-67, 260,
261, 269-70, 272, 412-13, 759; studies

action of solar spectrum on daguerreo-
type plates, 263, 264, 267, 457; makes
first daguerreotype portraits, 271-72,
273. 274, 355, 759
Dresden Ika Co., 442
Dreyer, Alois, Franz von Kobell. . ., 797
Driffield, Vero Charles, 450, 452, 453-54;
Photochemical Investigations and a New
Method of Determination of the Sen-
sitiveness of Photographic Plates (with
Hurter), 454

Drummond, Thomas, 528
Drummond’s calcium light, 386, 528-29
Drums, used in early motion pictures,
500, 504, 513

Dry plates, see Plates, dry
Dschabir ibn Hajjam, see Geber
Duboscq, Louis Jules, 54, 357, 373, 381,
382,^ 387, 388, 390, 474, 499
Duchatel (French Minister of the In-
terior), 230, 231, 232
Ducom, Jacques, 396
Ducos du Hauron, Alcide, 646, 647, 653;
Traite pratique de pbotograpbie des
couleurs (with Louis Ducos du Hau-
ron), 466, 643, 648, 653; Les Couleurs
en pbotograpbie et en particulier I'helio-
cbromie au charbon, 643; Pbotograpbie
des couleurs, 643; La Triplicite pho-
tograpbique des couleurs et I’impri-
merie, 643

Ducos du Hauron, Louis, 465, 467, 514-15,
642-49, 651-53, 658, 785, 807; Traite
pratique de pbotograpbie des couleurs
(with Alcide Ducos du Hauron), 466,
643, 648, 653; Les Couleurs en pboto-
grapbie, 643, 644, 648, 656, 808; La Pbo-
tograpbie indirecte des couleurs, 643,
648; L'Heliochromie, 648
Duda, Franz, 527
Dufay, 662

Dufay, Captain, 85, 100
Duhamel du Monceau, 12-13, 93> 73°. 7 3 1 ;
Quelques experiences mr la liqueur
color ante que foumit le pourpre . . . , 12
Du Hauron, see Ducos du Hauron
Duhousset, Captain, 502
Dujardin, 379, 595, 652
Dulk, Friedrich Philipp, 180-81; De lucis
effectibus chemicis, 180
Dumas, Jean Baptiste, 192, 224, 262, 272,
412

Dumont, R., 549

Dumoulin, Eugene, Les Couleurs repro-
duces en pbotograpbie, 648
Dunker, J. H. A., Pflanzenbelustigung

INDEX

oder Anweisung, 34
Dupuis, 383

Dusting-on processes, 566-67, 591
Dutkiewicz, 708

Dyeing: purple, 8-14; experiments in, 92-

93, 114, 1 1 5, 188, 189, 190-92

Dyes: used in color-sensitizing, 457-61,
464-78; confiscation of German patents
for, 477; used as desensitizers, 478-84;
produced with diazo compounds, 550-51
Dyes, mordant, see Mordant-dye process
Dynar lens, 41 1

Earinus, 5-6

Eastlake, Sir Charles, 321, 678
Eastman, George, 380, 432, 440, 486-92,
520, 695, 786

Eastman Dry Plate & Film Company, 440,
488

Eastman Kodak Company, 442, 447, 490-

94, 518, 524, 655, 673, 698, 718; Abridged
Scientific Publications from the Re-
search Laboratories, 696; Monthly Ab-
stract Bulletin of the Kodak Research
Laboratories, 696

Eastman Kodak Research Laboratory, xi,
378, 478, 695-96
Eberhard, G., 457

Ebermaier, Johann Edwin Christof, 122,
123, 124, 126, 127; Versuch einer Ge-
schichte des Lichtes, v, 122, 146, 729;
Commentatio de lucis in corpus human-
um vivum praeter visum efficacia, 122
Ecker, H., 656

Ecole des Arts et Metiers, 677
Ecole Municipale Estienne, 677, 812
Ectypa, 35

Eder, Josef Maria, 682, 688-91, 720-28;
Geschichte der Photochemie, vi; Aus-
fuhrliches Handbuch der Photographie,
vi, vii, 722; Geschichte der Photo-
graphie, vii, viii, ix, xi, xiii, 26; investi-
gations in spectroscopy, 14, 472, 532,
724; Quellenschriften zu den friihesten
Anfangen der Photographie, 25-26, 30,
63, 724, 733; Johann Heinrich Schulze,
631 73. 83, 724, 738; investigations in
photometry, 165, 418, 452, 453, 721, 722,
783; Die Daguerreotypie und die An-
fange der Negativphotographie auf
Papier und Glas (with Kuchinka), 252,
316, 757; investigation of nitrocellulose,
343-44; investigation of cadmium double
salts, 362, 720; Die Photographie mit
Kollodiumverfahren, 363; Die Bleiver-
starkung, eine neue Verstarkungsmeth-
ode (with Toth), 364; investigation of

829

intensifies, 364-66, 720; “Die Reaktion
von rotem Blutlaugcnsalz auf metall-
isches Silber,” 364; “Neue Untersuch-
ungen iiber die Bleiverstarkung,” (with
Toth), 364; Die Photographie mit Brom-
silbergelatine-Evtulsion, 365, 414; inves-
tigations in Roentgen photography,
384-85; Versuche iiber die Photographie
mit Rontgenstrahlen (with Valenta),
384-85; Jahrbuch fur Photographie und
Reproduktionstechnik, 388, 722; “Die
photographischen Objective” (with
Steinheil), 405; Momentpbotographie,
407, 624, 722; investigations in ammonia-
cal ripening of emulsions, 429-30, 778;
Theorie und Praxis der Photographie
mit Bromsilber gelatine, 430, 721; “Bei-
trage zur Photochemie des Bromsilbers,”
430; Modem Dry Plates, 43 1 ; introduces
iron oxalate developer, 433-34, 721,
780; introduces pyrocatechin devel-
oper, 434; introduces chemical devel-
opment of gelatine silver chloride emul-
sions, 443-45, 447, 721, 780, 781; Die
Photographie mit Chlor silber gelatine
(with Pizzighelli), 444; introduces gel-
atine silver bromo-chloride emulsions,
447, 721; Ein neues Graukeil-Photo-
meter fur Sensitometrie, 453; introduces
orthochromatic erythrosin plates, 469-
70, 722, 785; Beitrdge zur Photochemie
und Spektralanalyse (with Valenta),
470, 471, 472, 532, 724, 814; Rontgen-
photographie (with Valenta), 472;
Atlas typischer Spektren (with Valen-
ta), 472, 532, 724; investigation of pho-
tography with chromates, 559, 795;
Vber die Reaktionen der Chromsaure
und der Chromate auf Gelatine, Gum-
mi, Tucker und andere Substanzen,
559, 720; “Die Erfinder des Gummi-
druckes,” 560; Daguerreotypie, Talbo-
typie und Nieppotypie (with Kuchin-
ka), 692; Die chemischen Wirkungen
des far bigen Lichtes, 721; Die Bestim-
vrung der Salpetersdure, 720; Unter-
suchungen iiber Nitrozellulose, 720;
“Analysen des chinesischen Tees,” 720;
Bleichen von Schellack, 720; Rezepte,
Tabellen und Arbeitsvorschriften fiir
Photographie und Reproduktionstech-
nik, 723, 806; Ober Schloss Miinichau
bei Kitzbiihel in Tirol, 725; Beitrdge
zur Kenntnis des Einfiusses der chem-
ischen Lichtintensitdt auf die Vegeta-
tion, 725; “Licht, chemische Wirkung-
en,” 725; "Geschichte der Oester-

INDEX

830

Eder, Josef Maria ( Continued )
reichischen Industrien,” 725; “Petz-
vals Orthoskop,” 763; “Blaues Licht fiir
Portrataufnahmen bei kiinstlichem
Lichte,” 769; “Ober die Einwirkung von
Ferrizyaniden auf metallisches Silber,”
770; “Das Reifcn dcr Bromsilbcrgcla-
tine,” 778; “Zur Geschichte der ortho-
chromatischen Photographie mit Ery-
throsin,” 785; Cber das Verhalten der
Haloid- Verbindungen des Silbers . . .
785; “Versuch der Wiederbelebung
durch Hubert Herkomer und Henry
Thomas Cox,” 797; “Beitrage zur Ge-
schichte und Theorie der Algraphie,”
803; Karl Kampmann, 803
Edison, Thomas Alva, 489-90, 500, 509,
515. 518-19, 650-51, 718-19
Edwards, B. J., 445, 658
Edwards, Ernest, 619
Eggert, John, 662, 687, 695
Egli, Carl, 434

Egloffstein, Frederik von, 627; Abridge-
ment of Specification Relat. to Phot.,
805

Egypt, Nubia, Palestine and Syria, 332
Ehrenberger, 53

Einstein, Albert, photochemical law of,
418-19

Eisenlohr, 367
Ektypography, 804

Electrochemical theory, Berzelius', 167
Electrography, 260, 268, 574, 575, 581
Electrotachy scope, 513
Electrotyping, 568, 569, 574-75; see also
Photoelectrotypes
Element, defined by Boyle, 30
Elliot, James, 381
Ellis, Joseph, 206, 207
Emerson, P. H., Naturalistic Photography
for Students of the Art, 350
Emmerich, G. H., 693
Empedocles, 3

Emulsions, collodion: 376-79; silver bro-
mide, 377-79; orthochromatic, 378; iso-
chromatic, 379

Emulsions: gelatine silver bromide, 421-
38; gelatine silver chloride, 443-49; gela-
tine silver bromo-chloride, 447-48;
“grainless,” 668, 670-71
Enamel, positives on, 347, 566-67
Enamel process, halftone, 635, 806
Endlicher, 245, 281
Energiatype, 326

England, photography in, 677-79
English Autotype Company, 558, 559
English Cartographic Institute, 615

English Colour Snapshot Co., Ltd., 647
Engravings: Niepce’s method of copying,
221-22; as book illustrations, 33
Enlargements, 271, 324, 391-93
Eosin, sensitizing effect of, 379, 464, 466-68,
784; see also Erythrosin
Epicurus, 3
Epidiascope, 391
Episcopic projection, 54, 55
Erdmann, Friedrich Andreas, Griind-
licher Gegensatz auff das Griindliche
Bedencken und physikalische Anmerck-
ungen von dem todtlichen Dampfe der
Holtz-Kohlen, 71
Ericsson, Tore, 702

Ermenyi, L., 761; Petzvals Leben und
V erdienste, 303, 761, 762; “Theorie der
Tonsysteme von Petzval,” 762; “Nach-
tragliches ubcr Petzval,” 763
Ernemann, 411, 524
Ernemann, Heinrich, 687
Erythrosin, use in color-sensitizing, 469-

7 L 785.

Eschinardi, Francesco, Centuriae optical
pars altera, 52
Estanave, E., 669

Etching: galvanic, 576, 577-79; of daguer-
reotypes, 577-80, 591; Talbot’s inven-
tion of photographic, 582, 583, 593-94;
on steel, 591-94; on glass, 616-17; on
zinc, 621-25, 635

Etching, heliographic, see Heliogravure
Etching machines, 633, 806
Ethyl red, as a sensitizer, 473-76
Ettingshausen, Andreas Freiherr von, 245,
280, 281, 290, 293, 296, 311, 329
Ettingshausen, C. V., Physiotypia Plan-
tarum Austriaearum (with Pokorny),
570, 571, 796; Photographisches Al-
bum der Flora Dsterreichs, 796; Die
Blatt-Skelette der Dikotyledonen. .
796

Euclid, 1, 45, 46, 581

Eudoxia Macrembolitissa, 10- 11

Euler, Leonhard, 54, 120, 123, 130, 144, 706;

Letters on Various Subjects, 744
Euryscope lens, 407, 408
Evans, Mortimer, 515, 517
Excursions daguerriennes, 179, 578, 798
Exhibitions, photographic, 676, 680, 683,
684, 685, 702, 708, 715, 725
Exner, Wilhelm Fr., 689-91, 697; Erleb-
nisse, 814

Exposure, length of: in heliography, 223,
234; in daguerreotypy, 236, 254, 271,
275-78; in other photographic processes,
439

INDEX 8 3 1

Exposure meters, 449, 758; see also Pho-
tometers

Ex osure tables, 41 j, 450
Faberius, 7

Fabre, C., T raite encyclopedique de pho-
tographic, 26
Fabricius, 533

Fabricius, Georg, 24, 25, 26; De metallicis
rebus, 25

Fabroni, Giovanni Valentino Mattia, 119;
Di unatinta stabile che qui suo entrarci
daWaloc soccotorima, 744
Fabry, M. Ch., 694
Falk, Benjamin, 441
Faraday, 171, 642
Fargier, 557, jj8

Farmer, E. Howard, 438, 564, 565, 780, 795
Fanner, H. F., 562, 795
Farmer’s reducer, 366, 438
Fawcett, Samuel, 601
Feer, Adolf, 550, 551
Fehling, Neues Handworterbuch der
Chemie, 725

Feldhaus, F. N., 337; Leonardo der Tech-
niker und Erfinder, 734
Felisch, A., 708
Fenton, Roger, 359, 582
Ferdinand 1 , Emperor of Austria, 246, 247
Fembach, Die enkaustische Malerei, 730
Ferran, 442, 485

Ferricyanides, use in intensification, 364,

365

Ferner, A., 347, 351, 373
Ferrotypes, 326, 369, 370, 371
Feuerbach, 780

Fiedler, J., 183-84; De lucis effectibus
chemicis in corpora anorganica, v, 62,
183

Field, George, 186; Chromatographic, 187
Figuier, Louis, Exposition et histoire des
principal decouvertes scientifiques
modemes, 223
Film, origin of term, 786
Film-roll holder, see Roll holder
Films, 452, 485-94: stripping, 346, 362, 380,
485, 488, 489; celluloid, 485-86, 489-91,
492-93; roll, 486, 488-90; paper, 488;
transparent, 489

Films, motion picture: 470; use of per-
forated, 518; standard sizes of, 524
Filmtechnik, 695

Filters, 367, 388, 465-66, 469, 641; blue
glass, 355, 356; complementary light,
645-46; jee also Photography, three-color
Fiorelli, Kleine Schriften, 730
Firmicus Matemus, Julius, 15, 731

Fischer, Carl, Geschichte der Physik, v,
734; Physikalisches W orterbuch, v
Fischer, F., 471

Fischer, G. T., Photogenic Manipulation,
.356

Fischer, Nicolas Wolfgang, 160-62, 163,
164,- 173, 176, 181, 748-49; “Kritik der
von dem Herm Professor David Hieron
Grindel fortgesetzten Versuche liber die
kiinstliche Bluterzeugung,” 160; Vber
die Wirkung des Lichtes auf Hom-
silber, 160; “Ober die Ausscheidung des
Silbers aus dem Chlorsilber durch Zink,”
162; Vber die Natur der Metallreduk-
tionen, 176

Fishenden, R. B., 549, 678
Fixatives: lack of knowledge of, 97, 137,
139, 140, 141, 180, 182, 195, 196, 199, 254;
hyposulphites as, 170, 254, 757-58; Tal-
bot’s use of, 3:9-21, 323; development
after use of, 368

Fixing baths, 254, 538-39; for gelatine dry
plates, 437-38

Fizeau, Hippolyte Louis, 270, 457, 578, 580,
758; gold toning of daguerreotypes by,
254, 537; studies varied effects of light
on daguerreotype plates, 266-67, *69,
528; Vervielfaltigung der Lichtbilder
durch Abziehen einer galvanischen
Kopie eines Daguerreotyps, 798
Flach, H., 11; Herr Wilamowitz-Mollen-
dorf und Eudokia, 1 1 ; Die Kaiserin
Eudoxia Makrembolitissa, 730
Flashlight powders, magnesium, 474, 531-
33

Flower infusions, light-sensitivity of, 159
Fluorotype, 326

Fockeday, Hippolyte, Album photo-
graphique de Vartiste et de I’amateur
(with Blanquart-Evrard), 332
Focus, 703
Fontaine, 586, 587

Forch, C., “Edison and His Connection
with Cinematography,” 718
Fordos, Mathurin Joseph, 254
Forest, Lee de, 790
Forster, J. R., 98, 99
Forster, L. V., 773
Fortier, 486
Fothergill, 375

Fotografiske Forening, 703-4
Fotografiske Forenings Tidende, 704
Fotohandel, 703
Fotel printing, 549-50
Fotovreugde, 703

Foucault, Leon, 54, 387, 772-73; studies
varied effects of light on daguerreo-

INDEX

832

Foucault, Leon ( Continued )
type plates, 266-67, 2 ^9> 528; experi-
ments in astrophotography, 270, 392,
457; Atlas d'anatomie microscopique
(with Donne), 387

Fouque, S., 195, 200, 201-2, 204, 205, 206;
La Verite sur ['invention de la photo-
graphic, vi, 199, 201, 752, 753
Fourcroy, A. Fr. de, 1 1 5, 124, 152; “Sur
les differents etats du sulfate de mer-
cure,” 743

Fowler, R. J., 306, 418
Fox Talbot, see Talbot, William Henry
Fox

Foye, 270
Fransais, 406

France, photography in, x, 676-77
Franciscus Maurolycus, Photismi de lu-
mine et umbra, 43

Francke, August Hermann, 64, 65, 72

Frank, 187

Frank, Gustav, 710

Frankfurt Verein zur Pflege der Photo-
graphic, 683

Franklin, Benjamin, 87, 100, 397
Franklin Institute at Philadelphia, 680
Franz, L., 406

Fraunhofer, Joseph von, 50, 132-33, 251,
290, 292, 298, 308-11, 763
Fraunhofer lines, 132, 133, 264, 267
Freiburger Zeitung, 606
Fresnel, 157

Freund, Leopold, xi, 127, 723; Verges-
sene Pioniere der Lichttherapie, 123
Freymann, 574
Friebes, 707

Friedliinder, P., 14; Vber den antiken
Pur pur von Murex brandaris, 731
Friedlein, 557
Friedrich, Anton, 304, 763
Friese-Greene, William, 515, 516, 517, 518,
658, 790

Frisius, Gemma, 40
Fritz, Felix, 23, 28, 32, 67, 68, 81
Fritz, Georg, 803; Festschrift zur Enthiil-
lungsfeier der Gedenktafel fur Paul
Pretsch, 798; “Die Vorlaufer des Drei-
farbendruckes und der Farbenhelio-
gravure,” 807
Fromberg, 165
Fry, P. W., 346
Fulgur printing, 549

Fulhame, Mrs., 116-17, n8, 743-44; An
Essay on Combustion, 116
Fiilop-Miller, Rene, Die Phantasiemachine,
5 1 9

Fulton, Robert, 209, 754

Funke, C. R., 36
Fyfe, 335, 766

Gabriel, C. M., Recueil des travaux
scientifiques de Leon de Foucault (with
Bertrand), 773
Gaedicke, J., 474, 532
Gaillard, E., 634, 656
Galen, 46, 381

Gallic acid, 339, 340, 341; use of, by Tal-
bot, 322-23
Galvanography, 574
Gamble, Charles William, 678
Gamble, William, xiii, 767, 769, 777, 805
Ganz, R., 705

Garnett, Life of Maxwell (with Camp-
bell), 807

Gamier, Henri, 543, 556, 557, 566, 567,
595, 800
Garot, 7j 1
Gatel, 391
Gaudin, Alexis, 255

Gaudin, Marc Antoine, 266, 278, 314, 342-
43t 376-77, 421, 529, 763, 771; Dernier s
perf ectionnements apportes au daguer-
reotype (with Lerebours), 763
Gaumont, J., 509, 522, 658
Gaumont-Demeny, 522
Gauthier, Emile, see Cros, Charles
Gay-Lussac, Joseph Louis, 151-53, 155,
1 56-57, 158, 163-64, 176; “Dc la nature
et des proprietes de l’acide muriatique,”
152; Recherches physico-chimique, 156;
report on daguerreotypy to French
Chamber of Peers, 153, 232, 241-45
Gazzetta della fotografica, La, 700
Gebauer, 772

Geber (Gabir), 17, 22, 29; De inventione
veritatis, 22, 732; Curieuse vollstiindige
chymische Schriften, 732
Gehlen, Adolph Ferdinand, 120, 147, 148,
767; Physikalisches Worterbuch, 120;
Ober die Farbenveranderung der in
Ather aufgelbsten salzauren Metallsalze
durch das Sonnenlicht,” 746
Geiger, 730

Geissler, Friedrich, Baum des Lebens, 732
Geitel, Max, Der Siegeslauf der Technik,
7 2 5

Gelatine: early failures with, 339, 340,
421-22; use on collodion plates, 373-74;
use in emulsions, see Emulsions
Gelatine silver bromide, 425-32, 432-36,
439-43; firms producing plates, 427, 428,
430, 431-32; technical literature on, 430;
developers for plates, 432-36; printing
papers, 439-43, 607-8

INDEX

Gelis, Amadee, 254
Gemoser, Max, 619

Gerlach, J., Die Pbotographie als Hilfs-
mittel mikroskopisclier Forscbung, 773
Gerland, F. J. M., 624
German Society of Friends of Photog-
raphy, 683

Germany: early interest in daguerreotypy
in, 284-86; photography in, 680, 683-87
Gerson, Levi ben (Leon de Bagnois),
“De sinibus, chordis et arcubis,” 38
Gertinger, 362

Gesner, Konrad, 704; De onmi rerum
fossilium genere, gemmis, lapidibus,
met alii s, 24

Gibson, Charles R., 63, 92, 317, 319; Pho-
tography as a Scientific Implement,
322, 760

Gibson, K. S., 694

Giessendorf, Karl von, 61 1, 623, 802
Gilbert, 161, 730, 747
Gillot, Charles, 622

Gillot, Firmin, 576, 585, 621-22, 623, 624
Gillotage, 621, 622
Giphantie, 89, 90
Girard, Aime, 368

Girard, Jules, Recherches theoriques et
pratiques sur la formation des epreuves
photograpbiques positives (with Da-
vanne), 538

Giroux, manufacture of cameras with
Daguerre, 250-52
Giroux et Cie., 281, 285
Girtaner, 12 1; Anfangsgriinde der anti -
pblogistiscben Theorien, 117
Glaisher, James, 395

Glaserei fiir photographische Trocken-

f datten, 432

ass, 155, 185-86, 309; reproduction of
designs on, 135-39, 222 ; negatives on,
338-40, 344-45, 369, 485; direct positives
on, 369; types used in lenses, 408-10;
etching on, 616-17

Glauber, Johann Rudolf, 23; Explicatio
miraculi mundi, 23; Opera cbymica, 23,
106

Glotz, Wilhelm, 793

Glover, 376

Glover and Bold, 769

Gmelin, J. Fr., Geschichte der Chemie, v,

7 22 - . 73 2 > 737
Gobelins tapestry, 190
Goddard, John Frederick, 265, 275, 276,
278, 288, 759, 760
Goddard, Paul Beck, 265, 288, 759
Goeppert, Heinrich Robert, 772
Goerz, 695

8 33

Goerz, Carl Paul, 409, 410, 41 1, 474, 520,
776

Goerz-Festschrift, 776
Goethe, 37-38, 153-54, ! 77 i 748; Geschich-
te der Farbenlehre, 37, 153-54, 7 2 9;
studies on science of color, 153-55;
Reinecke Fuchs, 420
Goetz, Fritz, 633

Gold: alchemists’ work with, 15-22; use
in toning-fixing baths, 254, 537-38, 781-
82; Miethe’s attempts to transmute mer-
cury into, 475

Goldberg, Emanuel, 453, 773, 777; “Die
Herstellung neutral grauer Keile und
verlaufender Filter fiir Photometrie und
Photographic,” 783
Goldmark, Joseph, 412
Gold salts, light-sensitivity of, 18, 22
Goode, 528, 529

Goodwin, Hannibal, 486, 492-94; suit
against the Eastman Company, 492-94
Goodwin Film & Camera Company, 493
Gottling, 101, 1 16, 742; Beitrag zur anti-
phlogistischen Theorie, 743
Gould, 270

Goupil, Adolphe, 279, 559, 595, 653
Goupil & Co., 588

Government departments, as patrons of
photography, 694-95, 709-10, 712
Government Printing Office (Vienna),
568-72, 581, 656, 693, 694
Graff, 186
Grant, Alonzo, 531

Graphische Gesellschaft in Berlin von
Dr. E. Mertens & Co., 605
Graphische Lehr- und Versuchsanstalt
(Vienna), 471, 677, 683, 688-92, 723, 725
Granmuller, Neue Metbode von natiir-
lichen Pflanzenabdrticken in- und aus-
landischer Gewdchse, 35
Gravesande, s’, Pbysices Elementa Matbe-
matica, 53

Grebe, C., 629; “Geschichte der Raster,”
805; “Zur Geschichte der Dreifarben-
synthesen,” 807

Greene, William Friese-, see Friese-
Greene, William
Gren, 116

Grevius, Anatomia plantarmn, 55
Griendel, Franciscus, 53
Griess, P., 550

Grimaldi, Francesco Mario, 144

Grindel, 173

Grinten, van der, 793

Griswold, 370

Gropius, Carl, 214

Gros, Baron, 279

INDEX

834

Gros, D., 675
Grotthuss, Theodore von, 166-68, 642, 673,
707; Ober die chemische Wirksamkeit
des Lichtes, 167; law of photochemical
absorption, 166-68, 418-19; Physisch-
chemische F orsckungen, 749
Group pictures, taken by Daguerre, 315
Grove, 268, 335, 577, 578
Gruber, Dr., 816

Grand, Die Malerei der Griechen, 730

Griine, W., 566, 758

Guaiacum, 102, 157, 197

Guericke, Otto von, 31

Guemey, Sir Galsworthy, 528

Gueroult, Georges, 523

Guinand, P. L., 309

Guisac-Andre, 646

Guldber^, 41 3

Gum printing, see Printing, gum
Guncotton, 342-44, 347
Gun powder, 733
Gunther, Karl, 397
Gurney, 54
Gurtner, A., 655, 808
Giitle, J. Conr., Vber die Kupferstecherei,
34

Guy, Const., 600

Haack, Carl, 431, 779

Haas, Arthur, Atomtheorie, 420

Haas, J. C., 634, 636

Haase, Dr., 686

Haensch, 55

Hagemann, A., 102, 103, 197; Z ufdllige
Bemerkung, die blaue Farbe des Gua-
jacgummis betreffend, 102
Hahnemann, 1 1 5
Halation, 458

Halftone etchings, 583, 591-95, 596, 598
Halftone pictures, 586, 587, 589, 609- 1 3, 622
Halftone process, 623-38; early experi-
ments in producing, 626-30; Meisen-
bach’s use of single-line screen for, 630-
32; Ives’ use of cross-line screen for,
632; Levy’s use of improved cross-line
screen for, 633-35; use °f grain screens
for, 636-38
Hall, R. J., 549
Hall, V. C., 456
Halle, Joh. Sam., Magic, 106
Hallwachs, 419
Halm, E., 456
Hambock, Joh., 809

Hamer, “Recent Advances in Sensitizers
for the Photography of the Infra-red”
(with Brooker and Mees), 781
Hanfstangl, Edgar, 467, 559, 575, 599. 794

Hanfstangl, Franz, 559, 574, 575. 794. 797
Hann, 616, 803

Hansen, Fritz, 813; Die ersten Anfdnge
der Photographie in Berlin, 284
Hardwich, T. Frederick, 360, 535, 686;

Manual of Photographic Chemistry, 360
Hare, Robert, 288
Harff, 177
Harrison, C. C., 302

Harrison, G. B., “The Infra-red Content
of Daylight,” 781

Harrison, W. H., “The Philosophy of
Dry Plates,” 422

Harrison, W. Jerome, 422, 698; History
of Photography, vi, vii, 276, 347, 422,
759. 765. 799
Hart, F. W„ 531

Harting, H. H., 297, 298, 310, 410, 411;
“Zur Geschichte der Familie Voigt-
lander," 762

Hartmann, Franz, Cosmology, 21

Harap, Robert, 129, 133, 134, 745

Hasselkus, 411

Hauff, Fritz, 779-80

Hauff, Julius, 432, 435, 470, 695, 779

Hauler, Edmund, 4, 5, 6

Hauron, Ducos du, see Ducos du Hauron

Hawkeye camera, 491

Hay, Alfred, 727

Heat, effect distinguished from action of
light: 32, 60, 117-18, 124, 133-34; by
Schulze, 62, 74-75, 77, 82; by Scheele,
98; by Berthollet, 143; by Gay-Lussac
and Thenard, 152, 156-58; by Fiedler,
183-84

Heath, Charles, 799
Heaviside, 642

Hecht, Walter, “Das Graukeil-Photo-
meter im Dienste der Pflanzenkultur,”
777

Heeren, 342, 449, 777
Heid, 431

Heinlein, Photographikon, 809
Heinrich, Placidus, 57, 122, 125, 147, 157,
160, 161; Vber die Natur des Lichtes
(with Link), v, 145; Von der Natur und
den Eigenschaften des Lichtes, 729, 731;
Die Phosphoreszenz der Korper, 737
Helain, 539

Helbig, iVandgemalde der vom Vesuv
verschiitteten Stadte Ctrmpaniens, 730
Helcher, Hans Heinrich, Aurum potabile,
'7

Heliar lens, 410, 41 1
Heliochromatic camera, 645-46
Heliochromoscope, see Photochromo-
scope

INDEX

835

Heliochromy, 656, 665, 666
Helio-engraving, 628
Heliogravure (heliography) : Niepce’s in-
vention of, 193, 195, 218-23, 608; Tal-
bot’s method of, 204-5, 593"94; Breyer's
method of, 336-37; photoelectrotype
process of, 589-90; asphaltum method
of, 591-92; Klic’s improved method of,
596-99

Helioplastie, 585
Helioprint, 586

Hellenbach, Lazar Freiherr von, 19
Hellot, Jean, 63, 84, 88, 105, 106, 140, 534;
Sur une nouvelle encre sympathique,
84

Helmholtz, Hermann von, 366, 381, 640,
746; Handbucb der pbysiologiscben
Optik, 807
Henderson, 538
Henneberg, 560, 561
Hennicke, 181
Henry, 6
Henry, C., 190
Henry, Etienne Ossian, 176
Henry, William, 171
Heraclius, V on den Farben und Kiinsten
der Romer, 85
Heraeus, 533
Herlango, 431
Hermagis, 304, 305, 307
Hennbstadt, Bulletin des Neuesten und
Wissensitmrdigsten aus der Naturviis-
semcbaft, 151

Hermes Trismegistos, 16, 18, 29
Herodotus, 4

Herr, J., “Simon Stampfer, eine Lebens-
skizze,” 787

Herschel, Sir Friedrich Wilhelm, 128, 131,
■ 35 . 1 3«S, 146. 757

Herschel, Sir John Frederick William,
262-64, 335, 363, 542, 543, 673, 757-58,
777; discovers use of hyposulphites as
fixatives, 170, 254, 319, 320, 534, 757-58;
coins word “photography,” 258; studies
effect of solar spectrum on silver papers,
262-64, 457, 664; “On the Chemical Ac-
tion of the Rays of the Solar Spectrum
on Preparations of Silver,” 263; “On the
Action of the Rays of the Solar Spec-
trum on Vegetable Colours,” 263, 793,
812

Herschel effect, 263-64
Hertz, Heinrich, 642; Gottinger Nach-
ricbten, 807

Hertzberg, John, 396, 702, 814
Herz, Adolf, 705
Herzog, John, 432

Hesekiel, 545

Hess, Germain Henri v 176
Hessler, 747
Hewitt, C. H., 565
Heyde, 449

Hill, David Octavius, 327, 348, 349, 529
Hill, Levi, 316
Hillotype, 316
Hinterberger, Hugo, 688
Hipparchus, 3

Hirsch, Biograpbisches Lexicon der ber-
vorragenden Arzte aller Zeiten und
Volker , 80

Hittorf, J. W., 420, 421
Hochst Dye Works, 476, 477, 480, 481,
482, 483, 484
Hodgson, Richard, 387
Hoegh, Emil von, 410, 776
Hofei, Blasius, 621, 640
Hoff, F. van’t, 167, 419
Hoffmann, 574

Hoffmann, Friedrich, influence on Schulze,
66-71, 72, 73; Friderici Horrrmanni ob-
servationum physico-chymicarum, 67;
Eines beriibmten Medici griindlicbes
Bedenken und physikalische Anmer-
kungen, 70-71; De diaboli potentia in
corpora, 71

Hoffmeister, Philipp, 181-82, 286; “Von
den Grenzen der Holzschneidekunst,”
181

Holland, photography in, 703
Hollbom, 663

Hollenstein (caustic stone), 23
Homberg, Wilhelm, 31, 32, 33, 60
Homocentric lens, 411
Homolka, Benno, 474, 476, 481, 484, 551
Honey, use on collodion plates, 372
Hooke, Robert, 45, 53
Hooper, W., Rational Recreations, 45,
94; plagiarizes Schulze, 94-95
Hopwood, Henry V., Living Pictures,
789

Horgan, Stephen H., 628, 629, 630, 806
Horn, Ernst, 122-24, 1 25-27; Ober die
Wirkungen des Licbtes, v, 729
Horn, Wilhelm, 680
Homer, 500

Homig, Emil, 365, 427, 469, 681, 682, 683,
688, 812; Photograph. Jahrbucb, 812
Homsilver, 24, 25, 28, 150, 176; see also
Silver chloride

Horn's Pbotographisches Journal, 680
Horses in motion, photographic study of,

5 °'- 3 . 5 1 3
Hossauer, 285
Howard, B. Frank, 350

INDEX

836

Howletc, 583
Hrdlicka, Ferdinand, 431, 437, 536, 779
Hiibl, Arthur, Baron von, 401, 403, 468,
545, 547-48; Die Platinotypie (with
Pizzighelli), 546, 793; fosters graphic
reproduction processes at Military Geo-
graphic Institute, Vienna, 547-48, 561,
562, 590, 694; Die Reproduktionspho-
tographie im k. und k. Militargeograph-
ischen Institute, 547; Die photograph-
ischen Reproduktionsverf ahren, 547;
“Die Bestimmung der farbenempfind-
lichen photographischen Platten,” 783;
Der Platindruck, 793
Hufeland, 127

Hugersdorff, Autocartograpb, 403
Huggins, William, 366
Humboldt, Alexander von, 116, 756; Ver-
sucbe iiber die Zerlegung des Luft-
kreises, 743

Humphrey, S. D., 679
Humphrey's Journal of Photography and
the Allied Arts and Sciences, 679-80
Hunt, Robert, 325, 326, 340, 356, 362, 449,
457. 553. 745. 777! Researches on Light,
vi, 269, 326, 793, 812; A Popular Treatise
on the Art of Photography, 326; A
Manual of Photography, 326, 740, 793;
The Practice of Photography, 326;
Poetry and Science, 326
Hunter, Edgar, 798

Hurter, Ferdinand, 450, 452, 453-54; Photo-
chemical Investigations and a New
Method of Determination of the Sensi-
tiveness of Photographic Plates (with
Driffield), 454
Huse, E., 456

Husnik, Jakob, 618, 633, 803
Husnik and Hausler, 619, 637; Komauto-
typie mit ungefdrbtem Glasraster, 806
Husnik and Vilim, 654
Huxley, 387

Huygens, Christian, 31, 47, 50, 52, 120,
I2 3. 144. 703
Hyalography, 616-17
Hyalotypes, 340, 803
Hyatt, John W., 486, 786
Hydrotypes, 649
Hypo, 319, 320, 538, 539
Hyposulphites, property of, as fixatives,
170. 2 54. 757-58
Hyre, de la, see La Hyre, de
Hyslop, H. W., 635, 806

Ibn al Haitam (A1 Husen), 1, 2; “On the
Form of the Eclipse,” 37, 38
Ibn Ruschd (Averroes), 2

Ic a, 411

Ichwan Al Safa (Lautere Briider), 2
Iconographs, see Medals
Identification photography, 354
Idzerda, Leerbock der algemeene Foto-
grafie, 249

I. G. Farbenindustrie A. G., 478, 520
Illustrations: engravings as, 33; nature
printing used for, 33-36; photographs
as, 324, 331-33; Woodbury types as, 588,
589, 619, 799; printing of newspaper,
605-7; collotypes as, 619; halftone print-
ing of photographs for, 625
Imperial and Royal Institute for Teach-
ing and Experimentation in Photog-
raphy and the Reproduction Processes,
see Graphische Lehr- und Versuchs-
anstalt (Vienna)

Imperial and Royal Photographic Society,
see Vienna Photographic Society
Imperial Russian Academy of Sciences,
145, 706

Imperial Russian Office for the Production
of Government Papers, 709
Indigo, purple dye a derivative of, 14
Induction, photochemical, 413, 777
Infrared rays, 128, 146; chemical action
of, 155

Ingenhousz, Jan, 94, 125
Ink pictures, see Printer’s ink, photo-
graphic printing with
Instantaneous photography, 358, 370, 503,
506, 507, 508, 512, 524, 525
Institute d’Optique (Paris), 694
Intaglio printing, see Photogravure
Intensification, 265-66, 363-66
Interference-photochromy, 341, 461, 472,
668-72

Iodine, 162-64, 749; discovery of, 162;
properties of, 163, 164; use by Niepce
of, 220, 222, 223, 755
“Ionia,” 10-11
Iris, 623

Iron salts: light-sensitivity of, 56, 542;

printing methods with, 542-43
Isenring, Johann Baptist, 315, 704-5
Isochromatic collodion emulsions, 379
Istituto Chimico e Fotochimico, 700
Italy: early interest in daguerreotypy in,
286; photography in, 699-701
Ives, Frederick Eugene, 384, 629, 632, 633-
35.656.658-59,806,808
Ives, Herbert E., 384, 634; “Optical
Properties of a Lippmann Lenticulated
Sheet,” 669-70

Ivory: effect of silver nitrate on, 118;
light-sensitivity of, 151

INDEX

Jackel, George, 356

Jacobi, Moritz Hermann von, 568, 574,
707; Die Galvanoplastik, 568
Jacobsen, 383, 434

Jacquard looms, photographic produc-
tion of patterns for, 662-63
Jaccjuin, J. Fr. v., 289, 309
Jaffe, Arthur, Inc., 805
Jaffe, Max, 362, 619, 628, 629, 647, 805
Jaffe, Moritz, 628
Jagemann, 353
Jager, 383
Jager, Daniel, 121
Jagermaier, 359

Jahn, Johann Quirin, “The Bleaching and
Purification of Oils for Oil Painting,"
'43

Jahr, Richard, 671

Jahresbericht liber die Fortscbritte und
Leistungen im Gebiete der Photo-
graphie, 681
Jakobi, 545
Jakobsen, E., 460
James, Sir Henry, 614, 615
Jamin, 299
Janecek, Dr., 816

Janssen, Pierre Jules Cesar, 454, 506, 507,
788-89

Japan, photography in, 713-16, 817
Japan Photographic Annual, 714, 716
Japanese All Kanto Photographic Asso-
ciation, 714

Jasper, Friedrich, “Der Farbendruck in
Osterreich,” 640
Jedronoff, A., 709
Jena Christmas Eve tragedy, 69-70
Jena glass, 408, 409, 410
Jenkins, C. Francis, 515, 516, 522
Jermesite, light-sensitivity of, 180
Johnston, J., 424, 425
Joly, John, 661, 663
Jonas, 468, 799
Jones, Chapman, 452
Jones, L. A., 456, 491
Jordan, 449, 777
Joubert, F., 567
Jougla, 675, 695
Journal avantscene, 622
Journals, photographic, 676-713
Jovanovics, Anastas, 330, 765
Juch, 1 18; Versuch iiber die Wiederher-
stellung des Goldes, 744
Julius Pollux, Onomasticon, 10
Jumeaux, B., 660

Junius, Von der Malerey der Alten, 730
Junk, G. J., 442
Junk, Rudolf, 692

**37

Just, E., 441, 445, 446, 545, 781; Der Posi-
tive-Prozess auf Gelatine-Emulsions-
Papier, 446; Leitfaden fur den Positiv-
Entwicklungs-Prozess auf Gelatine
Emulsionspapier , 446

Kaiser, Heinrich, 461
Kaiserling, Lehrbuch der Mikrophoto-
graphie, 388
Kalle, 551, 793
Kallitype process, 543
Kamada, Yasugi, xi, 715, 716
Kamarsch, 342
Kamei, Katsujro, 660
Kampan Kabushiki-Kaisha, 715
Kampmann, Karl, 34, 617, 803; Die De-
korierung des Flachglases, 617; “Titel
und Namen der verschiedenen Repro-
duktionstechniken,” 800; “Geschichte
der Photolithographic mittels Umdruck-
papieres,” 802; Die graphischen Kiinste,
803; Die Literatur der Lithographic von
1198 bis 1898, 803; Geschichte der Litho-
graphic und der Steindrucker in Oster-
reich, 803

Kannegiesser, 285, 286
Kanolt, C. W., 384
Karabacek, 470

Karsten, 260, 268; “Literaturbericht der
Photochemie,” vi
Kasteleyn, 121

Kastner, 171, 188; Gewerbefreunde, 188
Kayser, Heinrich, Handbuch der Spec-
troskopie, 724
Kehrmann, 481

Keim, Die Miner almalerei, 730

Keller-Dorian, Albert, 672, 673, 811

Keller-Dorian-Berthon process, 672-73

Kelly, Life of John Dollond, 251

Kennett, Richard, 425

Kent, J. H., 488

Kenyon, G. A., 532

Kepler, Johannes, 31, 44

Kessler, H., 561

Kiewic, 805

Kilophot, 447

Kinetograph, 518, 718

Kinetoscope, 518, 519, 718-19, 790

King, J., 424

King, Samuel A., 394, 39J
Kingsley, 387
Kinora, 520

Kircher, Athanasius, 44, 46, 48-49, 31, 731;
Ars magna lucis et umbrae, 44, 48, 51,
5 2 t 735

Kirchhoff, Gustav Robert, 415, 416
Kirilow, A., “Physikalisches Institut in

INDEX

838

Kirilow, A. ( Continued )

Odessa,” 817

Kirwan, Richard, 98; On Phlogiston, 99
Kissling, John, 417, 777; Beitriige zm
kenntnis des Einflusses der chemischen
Lichtintensitdt auf die Vegetation, 418
Kite, aerial photography from, 396, 397
Klaproth, Martin Heinrich, 101, 197
Klein, 396

Kleinberg, Ludwig, Baron, 662
Klic, Karl (Karl Klitsch), 596-601, 637,
803; biography of, 596, 598-601 ; spell-
ing of name, 596-98; method of photo-
gravure invented by, 596-99, 800; roto-
gravure invented by, 599-601; firms
using processes of, 599, 601, 801; secrecy
of processes, 602, 603, 605, 607
Klic Photochemical Works, 597, 599
Klitsch, Karl (Kleitsch), see Klic, Karl
Klugel, 739

Knapp, Wilhelm, xi, 813
Kniphof, Joh. Hieron, 36
Knirim, Die Malerei der Alten, 186
Knofler, Heinrich, 640
Knop, 342

Kobell, Franz von, 286, 574, 575, 581; Die
Galvanographie, 574, 797
Kodachrome process, 655
Kodacolor, 673

Kodak, 489-91; origin of word, 489;
pocket, 490; folding pocket, 491; see also
Eastman Kodak Company
Kodak Abstract Bulletin, 491
Kodak-Eastman Works (Eng.), 491, 696
Kodak-Pa the Soc. Anon. Frang., 522
Kogel, Gustav, 551, 552
Kogel, J., 687

Kohler, August, 388, 391, 773
Kohler, Fritz, Forscher- und historiscbe
Bildnisse, 814
Kollmorgen, 41 1
Konig, A., 640

Konig, Ernst, 461, 473, 476, 477, 481, 482,
649, 6jy,Farbenphotographie, 476; Auto-
chromphotographie, 477; Arbeiten mit
farbenempfindlichen Flatten, 477
Kopp, H., Geschichte der Cbemie, 24, 732;
Beitriige zur Geschichte der Cbemie,
73i

Kopp, Raphael, 666
Koppe, A. K., 656

Koppe, C., 40 1 ; Die Fhotogr ammetrie oder
Bildmesskunst, 774; Fhotogr ammetrie
und Internationale W olkemnessung, 774
Koppmann, Gustav, 436, 564, 607, 655
Kraft, 59

Kraft and Steudel, 538

Krampolek, Andreas, 625
Kranseder & Co., 479
Kratochwila, Franz, 262, 265, 275-76, 278
Krayn, Robert, 557, 655
Kress, Georg Ludwig von, Die Galvano-
plastik fur industrielle und kiinstler-
ische Zwcckc, 576

Kreutzer, Karl Josef, 681, 682, 683, 813
Kries, 120

Kron, Erich, 454, 455, 456
Krone, Hermann, 373, 671, 686-87; Album
der Sdchsischen Schweiz, 771
Kronemann, Christian Wilhelm, Baron
von, 20, 732
Kronfeld, 776

Krumbacher, Karl, 1 1 ; Geschichte der
byzantiniscben Literatur, 730
Krumpel, Otto, 692
Kriiss, 54

Kuchinka, Eduard, .304, 692, 697; Die
Daguerreotypie und die Anfange der
Negativpbotographie auf Papier und
Glas (with Eder), 252, 316, 757; Die
Fhotoplastik, 692; Daguerreotypie, Tal-
botypie and Niepfotypie (with Eder),
692; “Geschichte der photographischen
Optik in Wien,” 762; “Die Sammlungen
der Graphischen Lehr- und Versuchs-
anstalt in Wien,” 814
Kuhn, Heinrich, 561

Kunckel, Johann, 59; Laboratorium chym-
icum, 737
Kurtz, 536

Kurtz, William, 464, 653, 654
Kyhl, Peter, 569

Laborde, Abbe, 361, 557
La Blanchere, de, 367; Monographic du
stereoscope, 383

Lacan, Ernest, 622, 752; Esquisses photo-
grapbiques a propos de VExposition
universelle, 279

Lucaze-Duthiers, H. de, 13; “Memoire
sur la pourpre,” 13

Lafollye, Depecbes par pigeons voyageurs
pendant le siege de Paris, 390
La Galls, Ad. Jul. Caesar, De phenomenis
in orbe lunae, 60
La Hyre, de, 34, 734
Lainer, Alexander, 431, 437, 545, 779; Lehr-
bucb der photographischen Cbemie,
437; Vortrdge liber photographische
Optik, 437; Photoxylographie, 437
Lainer effect, 437, 780
Lambert, 398
La Montain, 394
La Motte (Lamottc), de, 56, 101

INDEX

839

Lampa, Anton, 525

Lampadius, W. A., 189; Vber die durcb
Imponderabilien bewirkte Ver'ander-
ung ..., 188

Lamps, types used in projection apparatus,
53-55; see also Light, artificial
Lamy, E., 440
Landerer, 189

Landgrebe, George, Vber das Licbt, v,
180, 729, 731

Landriani, Count Marsiglio, 169, 170, 414,
449; “Di due termometri,” 169
Landscape photography, 299-300, 358
Lang, V. von, 374
Langenheim, Friedrich, 289, 340
Langenheim, Wilhelm, 289, 340
Langenheim brothers, 340, 803
La Payre, 127

Lard, action of light on, 151
La Rive, de 568
Larkin, 531

La Rue, Warren de, 270, 457, 584, 799
Lassaigne, 335

Lasteyrie-Dussaillant, Count Charles Phili-
bert de, 194

Latent images: discovery by Talbot, 321-
23; development after xation, 368
Latham, Woodville, 719
Laussedat, Aime, 398, 399, 400, 774; “Me-
moire sur l’emploi de la chambre claire
dans les reconnaissances topograph-
iques,” 399; La Metrophotograpbie, 774;
Recherches sur les instruments, les me-
thodes et le dessin topographiques , 774
Laviere, 600

Lavoisier, 100, 101, 144; System der anti-
phlogistischen Theorie, 740
Lea, Carey, 250, 261, 368, 377, 433, 460,
771; mordant-dye pictures made by, 363,
539; “Comparative Influence of Soluble
Chlorides, Bromides and Iodides on
Development,” 780
Leahy, 376
Lealand, 290

Leather bellows, Niepce’s construction of,
198

Le Blon, Jakob Christoph, 639, 640; 11
coloritto, 640
Leborgne, 529

Lebrun and Maes, portrait lens by, 307
Lechs, Etienne, 315
Le Comte, 127
Leggo, William August, 627
Leggotypes, 628

Le Gray, Gustave, 328, 340, 344, 345, 348,
363; Traite pratique de photograpbie
sur papier et sur verre, 344, 345, 537,

768; Photograpbie, 360, 765; Traite
nouveau tbeorique et pratique, 768
Legros, Encyclopedie de la Photographic,
360

Lehmann, Erich, 686; “Zur Geschichte
der Kinematographie,” 519
Lehmann, Hans, 524, 671, 672, 811; Bei-
trage zur Theorie und Praxis der direk-
ten F arbenphotograpbie nacb Lipp-
manns Methode, 671; Photographische
Rundschau, 671; “Beitrage zur Theorie
und Praxis der direkten Farbenphoto-
graphie nach Lippmann und Lumiere,”
8 1 1 ; “Interferenzfarbenphotographie mit
Metallspiegel,” 81 1; Die Kinematog-
raphie, 81 1 ; “Die Praxis der Interferenz-
Farbenphotographie,” 81 1
Lehr- und Versuchsanstalt fur Photo-
graphic, Lichtdruck und Gravure (Mu-
nich), 692

Leibnitz, Gottfried Wilhelm, 72, 706
Leipold, Joseph, 583, 585, 798
Leipzig Art Trades Academy and Art
Trades School, 693

Lemaltre, 199, 201, 204, 205, 206, 217, 591,
75 2

Lemercier, 555, 595, 608, 609, 610, 611
Lemercier & Co., 588
Lemery, 30, 31, 59, 60; Court de chymie,
30, 60

Lemery, the younger, in
Le Moyne, 340
Lenard, 419
Lenhard, Hans, 800

Lenses, 289-313, 403-12, 761; used by an-
cients, 2; used with camera obscura,
42-45, 198, 207, 214; used with projec-
tion apparatus, 47-54; used in Daguerre-
Giroux cameras, 251, 253, 255, 279;
Petzval’s portrait, 275, 290-97, 300-1,
304-6, 311-13; used by daguerreotypists,
280-89; PetzvaPs orthoscopic, 291, 292,
300, 301-2, 313, 403; construction of
large-size portrait, 304-7; construction of
aplanatic, 403-7; construction of anas-
ugmatic, 407-10, 775, 776
Lenta papers, 448
Lenz, Alfred von, Ucbatius, 498
Leo XIII, Pope, 426

Leonardo da Vinci, 33, 34, 40, 46, 734; on
nature printing from plants, 33; “Codex
Atlanticus,” 33, 39; description of

camera obscura by, 38-40
Le Prince, Louis Aime Augustin, 516, 717
Lerebours, N. P., 263, 298, 314, 315, 608,
609; Historique et description de la
daguerreotypie, 259; Excursions da-

INDEX

840

Lerebours, N. P. ( Continued )
guerriennes; vues et monuments les plus
remarquables du globe (with Rittner,
Goupil, and Bossange), 578, 798; Der-
nier s perfectionnements apportes au da-
guerreotype (with Gaudin), 763; Traite
de photographie (with Secretan), 764
Leroux, 129
Le Roy, 519, 719
Leslie, John L., 170
Lespiault, 363
Leth, Justus, 531, 567, 568
Lettelier, Augustin, 1 3
Leuco bases, 675, 730
Leutner, Aug., 447
Levy, Louis Edward, 633, 806
Levy, Max, 633, 634, 635
Lewald, August, 211-14; Gesammelte
Schriften, 211
Lewandowsky, L., 758
Lewis, William, 92, 107, 135; Commer-
cium pbilosophico-tecbnicum, 92
Lewitsky, 708
Licht, Das, 684
Lichtdruck, see Collotypes
Lichtenberg, 126, 616
Lieben, Philipp von, 790
Liebert, A., 530

Liebig, Justus, 180, 276, 278, 330, 717, 770
Liebreich, Oscar, 464
Liesegang, Franz Paul, xi, 51, 55, 195, 205,
383, 447. 448, 496. S°o. 514, 522, 787;
“Ausfiihrungen,” 41; “Schaustellungen
mittels der camera obscura in fniheren
Zeiten,” 42, 735; “Cber Christian Huy-
gens und die Zauberlaterne,” 47; Wis-
senschaftliche Kinematographie, 501;
“Die Camera obscura bei Porta,” 735;
“Der Ursprung des Lichtbilderappa-
rates,” 735; “Die altesten Projektions-
anordnungen,” 735; “Der alteste Pro-
jcktionsvortrag,” 735; “Die Camera ob-
scura und der Ursprung der laterna
magica,” 735, 736; “Die Projektionsuhr
•••.’’ 735! V om Geisterspiegel zum
Kino, 736; Z ablen und Quellen zur
Gescbicbte der Projektionskunst und
Kinematographie, 736, 772; Licbt und
Lampe, 736; “Uchatius und das Pro-
jektions-Lebensrad,” 788
Liesegang, Paul Edward, 352, 681
Liesegang, Raphael Ed., 674, 681, 687;
Beitrdge zum Problem des elektriscben
Femsebens, 420; Pbotographisches Ar-
cbiv, 674; Photograpbische Almanacb
fur tSyi, 674; “Zur Geschichte der
Farbenrasterplatten,” 809

Liesegang, Wilhelm Eduard, 329, 355, 686;
Handbuch der Photographie auf Kollo-
dion, 360; Verfahren zur Anfertigung
von Photograpbien, Ambratypen und
Sanotypen, 360

Light: early theories on nature of, v, 98-
99, 120-21, 123-25, 129-30, 144-47, 157;
definition of, i; study of, by ancients,
1-8, 31; effect on colors used in paint-
ing, 6-8, 85, 89, 186; effect in purple
dyeing, 8-14; wave theory of, 50, 120,
123, 144, 1 J7, 641-42; Bonzius’ experi-
ments with effect on colored ribbons,
88; biological effects of, 122-127; dis-
covery of law of interference of, 144,
746; Link’s and Heinrich’s dissertations
on, 145-47; electric transmission of, 420-
21; electromagnetic theory of, 641-42;
see also Phlogiston theory of light
Light, artificial: 53-55, 528-32; calcium,
53-54, 386, 528, 529, 532; first photograph
made by, 277, 288-89, 528; magnesium,
474.530-31. 532; Bengal, 528, 529; electric
arc, 528, 529, 530; incandescent gas, 533,
573. 7971 mercury-vapor, 533; electric
incandescent, 533

Light, chemical action of: 145-47, 1 78-79.
180-81, 183-84; early theories on, 91,
101, 129-30, 1 50-5 1; Priestley’s observa-
tions on, 93, 99-100; Scheele’s experi-
ments with, 96-99; Grotthuss’s theories
on, 166-68; Fiedler’s digest of discoveries
on, 183-84; see also Heat, effect dis-
tinguished from action of light
Light absorption, photochemical law of,
166-68, 418-19

Light intensity, measurement of, 112-13,
414, 415, 454-56; see also Photometers
Light reaction, photochemical measure-
ment of, 413-14
Lilienfeld, Leon, 537, 696
Limenci, Lanet de, 417
Limewater, blackening of chemical com-
pounds by, 91

Limmer, Fritz, 687, 749; Das Ausbleicbver-
fahren, 812

Linen: photographs on, 325, 791; positive
images on, 370

Link, Heinrich Friedrich, 125, 145, 146,
■47. 1 57. 160, 163. 164; Ober die Natur
des Licbtes (with Heinrich), v, 145;
Beitrdge zur Physik und Chemie, 117
Linnekampf’s Aristophot Co., 447
Linography, 325

Lipowitz, A., Die Daguerreotypie, 757
Lippmann, Edmund O. von, Entstebung
und Ausbreitung der Alchemie, 733

INDEX

Lippmann, Gabriel, 341, 461, 472, 668-70,
671, 672

Litchfield, R. B., Tom Wedgwood, the
First Photographer, 135, 745
Lithographtruste (Stockholm), 703
Lithography, 194, 550, 609, 613, 639, 797;

see also Photolithography
Lithophotographie; ou, Impressions ob-
tenues sur pierre a I’aide de la photo-
graphie, 609

Lithophotographs, see Photolithography
Littrow, von, 289, 290
Liverpool Dry-Plate and Photographic
Printing Co., 425, 427, 431
Liverpool Photographic Journal, 679
London Autotype Company, 562
London Photographic Society, 677
Lovejoy, Frank W., 492
Lowenstjem, Johann Kunckel von, 58-59
Lowig, 176

Lowy, Josef, 353, 407, 428, 461, 599, 602,
619, 636, 647, 656
Ldwy-Plener, 431, 469, 782
Lucenay, 529
Luckhard, Fritz, 353, 393
Lucretius Carus, 495
Lucs, de, 1 24

Lueger, Otto, Lexikon der gesamten T ech-
nik, its
Liihr, F., 778
Lumiere, La, 676
Lumiere, Antoine, 432
Lumiere, Auguste, 432, 511, 519
Lumiere, Louis, 432, 511, 519
Lumiere and Seyewetz, 436, 438, 478
Lumiere brothers, 432, 436, 612, 655, 670-
71, 675, 695; inventions in cinematog-
raphy, 500, 509, 510, 5 1 1, 512, 519-23,
719, 791; invention of autochrome

process, 661-62, 672, 809
Luminosity: disparity of optical and

chemical, 269, 529; of celestial bodies,
measurement of, 457
Luminous minerals, 57-60, 73; action of
solar spectrum on, 154
Luna cornea, 24, 28; see also Silver chloride
Lunar Society, 134, 135
Liippo-Cramer (Liippo Hinricus Cramer),
xi, 435, 476, 478-80, 484, 695; “Grund-
lagen der photographischen Negativver-
fahren,” 263, 368, 479, 786; “Ein neues
Verfahren, hochst-empfindliche und
selbst farbenempfindliche Platten bei
gewohnlichem Kerzenlichte zu ent-
wickeln,” 478; N egativentwicklung bei
hellem Lichte, . . ., 479; Photogra-
phische Probleme, 479; Kolloidchemie

841

und Photographic, 479; Kolloides Silber
und die Photohaloide von Carey Lea,
479, 771; Rontgenographie, 479; Das la-
tente Bild, 479; biography of Eder,
written by, 720-28
Luther Robert, 26, 687, 749, 777
Liittgens, J., 325
Lux, 703

Luynes, Duke of, prize competition by,
555-57. 676

Lynkeyoskope lens, 410, 776
Lyons, 576

Lyte, Maxwell, 363, 372, 538, 766

McCabe, Lida Rose, “The Beginnings of
Halftone, from the Note Books of
Stephen H. Horgan,” 630
McDonough, J. W., 660-61
Mach, Ernst, 452, 523, 525, 772; invention
of Roentgen stereoscope by, 384-85, 772;
photographic study of projectiles by,
524-26, 527; “Erscheinungen an fliegen-
den Projektilen,” 525; Die spektrale und
stroboskopische Unterscheidung tonen-
der Korper, 791; “Beitrag zur Mechanik
der Explosionen,” 791
Mach, Ludwig, 526, 791
Maclure, 621

Maclure and Macdonald, 625
Macpherson, 61 1

Maddox, Richard L., 422-24, 778
Maedler, Johann von, 259; Geschichte der
Hivnnelskunde , 259
Maemecke, 603, 604

Magic, application of chemical phenomena
to field of, 105

Magic lantern, 46-50, 51-55, 735; see also
Projection apparatus
Magic photographs, 264, 758
Magisterium argenti, 23
Magnesium Company, 531
Magnesium light, 474, 530-33
Magnus, Hugo, Die geschichtliche Ent-
wicklung des Farbensinnes, 730
Malagutti, Faustino Jovita, 414, 415, 449
Mallmann, F., 461, 785
Malone, 324

Maltese cross, use in motion picture pho-
tography, 500, 506, 516, 522
Manchurian Artistic Photographs group,
7‘5

Manganic salts, light-sensitivity of, 165

Manly, Thomas, 561

Manul process, 337

Maps, reproduction of, 590

Maps, photographic, see Photogrammetry

Marcilly, 600

INDEX

842

Marcy, 54

Marechal, Ch. Raph., 566, 617
Marey, Etienne Jules, 501-2, 507-12, jij,
520, 524, 789, 790; Developpement de
la methode graphique, 506, 789; La Pho-
tographic du mouvement, 508; Le
Mouvement, jii, 789; La Chronopho-
tographie, 788, 789; Du mouvement dans
les fonctions de la vie, 789; La Machine
animate locomotion terrestre et airienne,
789; Physiology medicate et la circula-
tion du sang, 789; Le Vol des oiseaux,
789; La Locomotion et la photographic,
789; Fonctions et organes, 789
Marggraf, Memoires de Berlin, 93
Marion, A., 358, 440, 561
Mariot, Emil (Schielhabel), 531, 562, 563,
589, 590, 613, 799

Mariotte, Ed., Traite de la nature des
couleurs, 55

Marktanner-Tumeretscher, Die Mikro-
photographie als Hilfsmittel naturwis-
senschaftlicher Forschung, 388
Marsh Brothers, 589
Martens, Friedrich von, 255, 329
Martin (professor), 54
Martin, Adolphe Alexandre, 369, 370
Martin, Anton, librarian at Vienna Poly-
technikum, 252, 280-81, 282, 293, 298,
312, 329, 680, 681; Reportium der Pho-
tographic, 245, 329, 33J, 680, 798; Hand-
buch der Photographic, 360; Htmdbuch
der Emailphot., 796; Repertorium der
Galvanoplastik und Galvanostegie, 797
Martius, Ernst Wilhelm, Neueste An-
weisung, Pflanzen nach dem Leben
abzudrucken, 34
Marvel drum, joo
Marville, Charles, 329
Maschek, Rudolf, 800
Mascher, I. F., 772
Maskell, Alfred, 560
Mason, A., 288
Masson, 742
Mather, W., 531

Mathet, T raite practique d e photomicro-
graphie, 388
Mathey, 805

Mathieu, P. E., 537; Auto-photographie,
537

Matschoss, Beitrdge zur Geschichte der
Technik und Industrie, 769
Matthews, E., “Processes of Photography
in Natural Colors, 664
Maul, Alfred, 397
Maurisset, 256

Mawdsley, Peter, 425, 427, 439, 440

Mawson and Swan, 427, 431, 433, 445, 487,
558

Maxwell, James Clerk, joo, 640-42, 656;
“On the Theory of the Three Primary
Colours,” 641; Treatise on Electricity
and Magnetism, 642
Mayall, J. E., 249, 314, 349
Mayer, La Photographic consideree
comme art et cornme Industrie (with
Pierson), 90

Mayer, Emil, 565, 685; Das Bromolver-
fahren, 565
Mazer, C. P., 702
Meade, Charles, 249

Medals: alchemic, 19-21 ; commemorative,
80, 249, 303; as photographic awards,
294, 676, 678, 680, 682, 683, 702, 715, 763
Medicines, preservation in colored bottles,
185-86

Mees, C. E. Kenneth, xiii, 491, 696, 773;
“Fifty Years of Photography,” 781;
“Recent Advances in Sensitizers for the
Photography of the Infra-red” (with
Brooker and Hamer), 781; “Motion
Pictures in Natural Colors,” 8 1 1 ; “Ama-
teur Cinematography and the Koda-
color Process,” 81 1
Megascope, 198
Megatypy, 387
Meggers, 694

Mehegard, E., Memorials of Wedgwood,
745

Meisenbach, Georg, 625, 630-34
Meisenbach’s Autotype Company, 631
Meisenbach, Riffarth & Co., 599, 604, 654,
805

Meissner, Traugott, 169, 170; Handbuch
der allgemeinen und technischen
Chemie, 169
Meissner & Buch, 656
Meister, Lucius & Pruning, 695; see also
Hochst Dye Works
Melainotypes, 370, 770
Melhuish, Arthur James, 331, 380, 488
Melsen, 525

Menard, Louis, 342; Dreams of a Heathen
Mystic, 343; De la moral avant les phil-
osophes, 768

Meniscus lens, 45, 132, 207, 294, 754, 756-57
Mente, O., 686; Unter der Sonne Ober-
agyptens (with Miethe), 475
Mentienne, La Decouverte de la photo-
graphic en 1839, 754
Meran, Albrecht Graf von, 524
Merck, C., 189
Mercuric sulphate, 1 16
Mercury bromide, light-sensitivity of, 176

INDEX

843

Mercury oxides, light-sensitivity of, 121,

1 z 9> '33

Mercury salts, light-sensitivity of, 83, 91,
"4-'5. '77

Mercury vapors, development by: 259,
260, 262; invented by Daguerre, 227-28,
250

Merkens, W„ 675
Mertens, Eduard, 603, 604, 6oj, 606
Merz, George, 290
Messter, Oskar, 522, 697
Metal chlorides, light-sensitivity of, 147
Metallic cloths, 1 16-18
Metals, alchemists’ attempts to transmute
base into precious, 15, 17, 21, 475, 733
Meteoric waters, investigation of, 172
Meters, exposure, see Exposure meters
Meteyon, Wedgwood and His Works, 745
Metternich, Clemens, prince, 245, 246, 247,
280, 318

Meydenbauer, Albrecht, 400; Das Denk-
malerarchiv und seine Herstellung, 774
Meyer, Bruno, Sacbverstdndiger und
deutsches Reichspatent, 808
Meyer, Hugo, 409, 41 1
Meyer, Johann, 766

Meyer, Jos. Fr., Cbymische Versuche zur
ndheren Erkenntnis des ungeloschten
Kalches, 91; investigation of caustic sub-
stances, 91

Meyer-Heine, H., La Photographie en
ballon, 774

Meyers Grosses Konversations-Lexikon,
384. 7 2 5

Meynard, 342, 343
Meynier, 538

Meynier, Joh. Heinr., Anleitung zur Atz-
kunst, 799

Mezzograph screens, see Screens, grain
Mezzo-tinto-gravure, 602
Microphotography, 385-88, 389, 508; see
also Photomicrography
Microprojection, 391
Microscope, projection, 54, 390-91
Miethe, Adolf, 461, 473, 474, 476, 532, 604,
657, 686, 773; Unter der Sonne Ober-
dgyptens (with Mente), 475; Photogr.
Aufnahmen vom Ballon aus., 774
Migursky, 707

Military Geographic Institute (Tokyo),

7! 6

Military Geographic Institute (Vienna),
547-48, 584, 590, 694

Military photography, see War photog-
raphy

Millet, 347, 529
Millon, 342

Mills, W. H„ 477, 483
Milmson, 485

Mirror writing, used by Leonardo da
Vinci, 39, 40
Mitscherlich, Eilhard, 176
Mittwald, 576
Mizaldi, Antonio, 35
Moestlin, 40

Moffit, “A Method of Aerographic Map-
ping,” 402
Moh, 485
Moignie, 357

Moigno, Abbe, 296, 381 ; Antique modeme,
382

Moisture, effect on dyestuffs, 190-92
Moitessier, La Photographie appliquee
aux recberches micrograpbiques, 773
Molard, Humbert de 514, 537
Moll, A., 347, 765

Molybdic acid, light-sensitivity of, 121
Molyneux, 50; Treatise of Dioptrics, 53
Monceau, Duhamel du, see Duhamel du
Monceau

Monckhoven, Desire Charles Emanuel
van, 393, 404, 425, 427-29, 460, 703, 778;
Traite general de photographie, 428;
Traite populaire de photographie sur
collodion, 428; Photographische Optik,
429; Instruction sur le procede au gela-
tino-bromure d’argent, 429, 430; Du
gelatino-bromure d’argent, 429
Monconys, M. de, 34, 736
Monfort, de, 529, 676
Monochromata, 7-8

Monpillard, La Microphotographie, 388,
“Notes sur l’histoire de la photomicro-
graphie,” 386

Mons, Jean Baptiste van, 150
Montabert, Traite complet de la peinture,
186

Montel, Paul, 677, 812
Montgolfier, 142
Montmeja, de, 677
Moon, photographing the, 269
Morch, 804; Handbuch der Chemigraphie
und Photochemigraphie, 804
Mordant-dye process, 363, 366, 539-42
Morgan and Kidd, 440, 485
Morhoffi, Oratio de laudibus, 732
Morienus, 29

Morse, Samuel Finley Breese, 272, 273,
274, 289

Mortimer, F. J., 565
Morton, Henry, 391

Moser, Ludwig Ferdinand, 260, 266, 268,
3 ®'

Motay, C. M. Tessie du, 5 66, 617

INDEX

844

Motion pictures, see Cinematography;
Serial photography

Motion Picture Trust of America, jij, j 18
Motte, de la, see La Motte, de
Mountain photography, 358-59
Movement, photographic analysis of: by
Muybridge, 501-5; by Janssen, 506; by
Marey, 507-12; by Anschutz, 512-13;
with slow motion pictures, 523
Mroz, B. J., 657
Mucklow, 452
Mudd, J„ 373, 375

Muggeridge, Edward James, see Muy-
bridge, Eadweard,

Mullay, John, 615
Muller, 396
Muller, G. A., 214
Muller, Heinrich Jacob, 366, 457
Munich: photographic lens production in,
403; teaching of photography in, 692-93
Muntz, Eugene, 39
Murdoch, William, 135
Muriatic acid, 161
Murray, 568

Murray (professor), 101
Murray, Sir James A. H., 258
Musee Dantan; galerie des charges et
croquis des celebrites de I'epoque, 257
Museums, see Photography, historical col-
lections of

Musger, August, 523, 524
Mustard oil, 378
Mutoscope, 522

Muybridge, Eadweard, 500-5, 507, 717,
718; The Horse in Motion, 503; Animal
Locomotion, 504; Descriptive Zooprax-
ography, 505; Popular Zoopraxograph,
505; Animals in Motion, 788
Mylbaus, C. S., 702

Nachet, 387
Nachet, C., 657

Nadar (Gaspard Felix Tournachon), 257,
393-94- 395. 5 2 9- 53>. 773-74J Paris pho-
tographe, 399
Nadhemy, A., 710, 814
Namias, Rodolfo, 366, 540, 541, 700; “The
Fixation of Coaltar Dyestuffs on Metal
Compounds,” 540, 700; “The Fixation
of Colors on Copper-Ferrocyanide
Images,” 540, 700; Manuale teorico-
practico di chimica fotograjica, 700; La
jotografia in colori, ortocromatismo
e filtri di luce, 700; / processi di illus-
trazione grafica, 700; “Direct Toning of
Silver Images with Copper Ferrocya-
nide and Ferrous Ferrocyanide,”/Oo;

“Photochemistry of Mercury Salts,”
700; “Direct Positives by Reversal with
Potassium Permanganate,” 700; “In-
fluence of Alkaline Salts of Organic
Acids on the Permanency of Bichromate
Preparations,” 700

Narbutt, Johannes, Vber den Herschel-
Effekt, 264

National Museum (Washington, D. C.),
698, 759

National Physical Laboratory (Tedding-
ton, England), 694
Natterer, Johann, 276, 759
Natterer, Joseph, 276-77
Natterer brothers, 275, 276-77, 278, 289,
528, 760

Nature-printing, 33-36, 568-73; see also
Electrotyping, Woodbury types
Neal, 445

Neblette, Carrol Bernard, Photography,
446. 447. 448, 449

Nederlandsche Amateur Fotografen

Vereeniging, 703

Nederlandsche Fotografen Patroons

Vereeniging, 703
Neff, Peter, 370

Negatives, photographic: invention by
Talbot, 316, 321-23, 340; experiments
with transparent glass for, 338-41, 344-45
Negre, Charles, 584, 592, 595, 622, 623,
798, 800, 804
Negrctti, 395

Nepera Chemical Company, 446
Nernst, W., 413, 419, 8r6
Nero, 2

Netto, F. A. W., 256; Vollstdndige An-
weisung zur Verfertigung daguerre-
scher Bilder, 252; Die kalotypische Por-
trdtkunst, 329
Neubronner, 390

Neue Photographische Gesellschaft (N.

P. G.), 441, 442, 485, 564
Neuhauss, Richard, 671, 674, 675, 749,
810-11; Lebrbuch der Mikrophoto-
graphie, 388; Die Mikrophotographie,
388; Photographic auf Forschungsreisen,
81 1 ; Anleitung zur Mikrophotographie,
8 11; Die Farbenphotographie nach dem
Lippmannschen Verfahren, 811; Lehr-
buch der Projektion, 811
Neumann, August, 281
Neumann, Kaspar, 83; Praelectiones Chy-
micae, 738

Newspapers: introduction of rotogravure
for, 605-7; halftone printing plates for,
628, 629-30
Newton, 378

INDEX

845

Newton, Sir Isaac: emission theory of
light advanced by, 31, 50, 98, 120, 123,
144; theory of solar spectrum advanced
by. 153. «i. 3°9.. 63?. 748
Nicotine, light-sensitivity of, 190
Niepce (colonel), 207-8
Niepce, Claude, 193-96, 199-200, 205, 206,

2 ,° 7

Niepce, Isidore, 193, 195, 200-2, 204-5, 2 3 °>
752, 753. 755-56; succeeds his father to
contract with Daguerre, 226-29, 233;
Historique de la iecouverte impro-
prement novimee daguerreotype, 227,
752; attempt to sell daguerreotype by
subscription, 229, 230; sale of daguer-
reotype invention to French govern-
ment, 230-32, 245; life pension from
French government to, 232, 240-41
Niepce, Joseph Nicephore, 102, 182, 193-
207; asphaltum process used by, 103,
197, 199, 200-4, 2 1 8- 2 3, 250, 608; experi-
ments with fixatives, 170, 197, 199; early
life of, 193-94; lithographic experiments
of, 194-95, 608; cameras used by, 195-96,
197; experiments with lenses, 198-99;
produces first photograph in camera,
200-3; heliographic reproductions on
metal invented by, 204-7, 2 ■ 8-23, 250,
591; “Memoire,” 205, 206; collaboration
with Daguerre, 207-8, 215-17, 224-26,
2 33; “Notice sur l’heliographie,” 218;
death of, 226; Daguerre’s use of inven-
tions by, 226-29; “On Heliography,”
754; see also Daguerre
Niepce-Daguerre Company, 201, 216-17
Niepce de Saint-Victor, Claude Felix
Abel, 338-39, 591-92, 611, 665-66, 752,
767; invention of glass negatives by,
338-39. 37 2 . 535; Recherches photo-
grapbiques, 338; Traite pratique de
gravure heliograpbique sur acier et sur
verre, 338, 592, 800
Niepceotypy, 338-40
Nihon Photo Industrial Co., Ltd., 715
Nihon Shashinshi Rengo Kyokai, 715
Nitric acid, 22; experiments by Priestley
with, 99; experiments with, 108-9
Nitrocellulose, 343, 344; use in making
transparent film, 489, 492-93
Nordisk Tidskrift for Fotografi, 701, 702,
814

Norris, Richard Hill, 373, 374, 375, 395

Nostitz, Count, 707-8

Nottone, 299

Novak, Franz, 635

Numismatics, 20, 79

Niinlicher und curieuser Kiinstler, 34

Oakten, C. H., 772

Obermayer, Oberst von, Geschichte der
tecbniscben Militar-Akademie, 498
Obermiillner, Adolf, 359
Obemetter, Emil, 536
Obemetter, J. B., 536, 567, 784
Obemetter-Perutz, 470
Objectives, see Lenses
Oehme & Graff, 286
Oettingen, “Abhandlungen fiber Elek-
trizitat und Licht von Theodor Grott-
huss," 749
Offord, 538
Offset process, 616
Ogura, K., 716
Ohm and Grossmann, 619
Oil prints, 562-63, 564-65; transfer of, 563
Oils, action of light on, 113, 130, 131, 143,
188, 189, 753
Oleography, 562
Olmsted, A. J., 698
Omura, Hitoshi, 716
Onesicritus, 4

Opoix, 100; Observations physico-cbym-
iques sur les couleurs, 740
Oppenheim, 456
Oppenheim, F., 816
Optical firms, see Lenses
Optical sensitizers, 458, 459, 465, 468, 652;

see also Color sensitizers
Optical Society of America, 696
Optics: study of, by Greeks, 1-3; Vienna’s
importance in history of, 307-13;
modern photographic, 403-12; see also
Lenses

Ordoverax, 549
Orel, E. von, 402, 403
Orell-Ffissli process, 611
Oriental Photo Industrial Co., Ltd.,
Tokyo, 715

Orthochromatic collodion emulsions, 378
Orthochromatic film, 490
Orthochromatic photography, 378, 459,
466, 469-70, 783
Orthochromatic plates, 469-70
Orthoscopic lens, 291, 292, 300-2, 313, 403
Orthostigmat lens, 407, 410
Ortmann, Max, 606

Osaka Industrial Experimental Station, 7 1 5
Osann, G. W., 576; Anwendung des
hydroelektrischen Stromes als Atzmit-
tel, 576
Osborne, 799
Osborne, J. W., 612, 614
Ost, Adolf, 529, 535, 536
Ostanes, 16

Osrwald, Wilhelm, 113, 675, 71 1; Far-

INDEX

846

Ostwald, Wilhelm ( Continued )

behatlas, 1 1 3; Lebrbucb der allgemeinen
Chemie, 778

Oxalates, light-sensitivity of metal, 95, 177-
78. 75 1

Oxygen, 116; Berthollet’s studies of, 107-
109, 1 14; importance to health, 127; im-
portance in dyeing, 190-92
Oxyn lens, 411
Ozalid process, jji
Ozobrome process, 562
Ozotype, 562

Paganini, Fotogrammetrie, 774
Painters, use of photography by, 348-49
Paintings: effect of light on colors used
in, 6-8, 85, 89, 186; reproduction of,
466-67, 469-70, 558-59, 574, 654, 802
Palaeokappa, Constantin, 1 1
Palladiotype papers, 544
Palmer, 448

Panchromatic film, 490

Panchromatic plates, 460-61, 473, 474, 475

Paniconographs, 576, 621, 623

Pannotypes, 369, 370

Panopticon, 719

Panorama camera, 255-56, 758

Panoramic photography, 255-56, 329, 396;

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